Development of a novel Z-scheme CoxNi1-xTiO3/CdS (x = 0.5) photocatalyst for the efficient degradation of organic pollutants via a visible-light-driven photocatalytic process

Herein, for the first time, we reported the synthesis of a novel Z-scheme CoxNi1-xTiO3/CdS (x = 0.5) heterojunction photocatalyst and the investigation of its visible-light-driven photocatalytic performance toward degradation of methylene blue (MB). The developed photocatalyst was structurally characterized by applying X-Ray diffraction analysis (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET), differential reflectance spectroscopy (DRS), and photoluminescence (PL) techniques. The results indicated the formation of a highly porous structure with improved visible light adsorption capacity, favorable for the catalytic activity. At an optimum condition of 10 mg/L of MB and 300 mg/L of catalyst, the ternary photocatalyst demonstrated a MB removal efficiency of 99 % after 75 min of the treatment process. The radical trapping experiments unveiled that hydroxyl and superoxide radicals were two main reactive species formed under visible light, while the valance holes possessed an insignificant role. The synergetic impact of the CoxNi1-xTiO3 (x = 0.5) and CdS on the photodegradation of MB over the as-prepared CoxNi1-xTiO3/CdS (x = 0.5) photocatalyst through Z-scheme photocatalysis was indicated by the results of the mechanism studies. The percentage impact of the treatment time, MB concentration, the ratio of CoxNi1-xTiO3/CdS (x = 0.5), and the dosage of catalyst using analysis of the CCD modeling was obtained as 47.04, 16.67, 7.22 and 0.87 %, respectively. Furthermore, the as-synthesized photocatalyst possessed high recyclability and photostability with only a 3 % decline in activity after four repetitive cycles.

Pioneering superior efficiency in Methylene blue and Rhodamine b dye degradation under solar light irradiation using CeO2/Co3O4/g-C3N4 ternary photocatalysts

In this research work, we have successfully synthesized the CeO2/Co3O4/g-C3N4 ternary nanocomposite for hydrothermal method for photocatalytic applications. The synthesized nanocomposites were characterized using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, Field emission scanning electron microscopy (FE-SEM), Transmission electron microscopy TEM, Photoluminescent spectra (PL), X-ray photoelectron spectroscopy (XPS), Brunauer- Emmett-Teller (BET) and Ultraviolet diffuse reflectance spectroscopy (UV-DRS) technique. As per the optical spectroscopic investigations CeO2/Co3O4/g-C3N4 ternary nanocomposite exhibited the high optical absorption range and its band gap is reduced from 2.95 eV to1.83 eV. The PL spectra showed the lowered emission peak intensity of ternary nanocomposite which is revealed that the better charge separation and slow recombination of electron hole pairs. The highest photocatalytic degradation efficiency of CeO2/Co3O4/g-C3N4 ternary nanocomposite showed 93 % and 86 % towards the pollutant methylene blue and Rhodamine B. Moreover, photodegradation of the pollutants followed pseudo-first order kinetics with a very high-rate constant of 0.02211 min-1 and 0.017756 min-1. Additionally, the ternary nano catalyst was delivered the remarkable stability performance even after five cycles. This research may provide a low-cost approach for synthesized visible light responsive catalysts for use in environmental remediation applications.

Preparation of reusable hydrogel spheres based on sodium alginate/Fe3O4 modified with carboxymethyl Huangshui polysaccharide and the efficient adsorption performance for methylene blue

This study successfully constructed a novel multifunctional bio-adsorbent using sodium alginate (SA), ferroferric oxide (FFO), and carboxymethyl Huangshui polysaccharide (CMHSP) with rapid separation, pH sensitivity, efficient adsorption, and reusability for enhancing the removal of methylene blue (MB) in wastewater. FTIR, XRD, SEM, and VSM results indicated CMHSP improved the porosity of the hydrogel spheres, thus significantly enhancing the MB adsorption capacity with the rate-limiting controlled by chemical adsorption, intraparticle diffusion, and film diffusion. The maximum adsorption capacity obtained from Langmuir model of SA-FFO-CMHSP (186.57 mg/g) was obviously higher than that of SA-FFO (178.82 mg/g). Thermodynamic results showed that the MB adsorption process was endothermic, spontaneous, and favorable, and physical adsorption was dominant. Remarkably, MB adsorption maintained 87% ∼ 95% of the initial after four adsorption-desorption cycles, and proper carboxymethylation was conducive to MB adsorption over a broader range pH. These findings provided reference for designing new efficient bio-adsorbents and the recyclable utilization of Huangshui by-products, which was of great value.

Integrating DFT and machine learning for the design and optimization of sodium alginate-based hydrogel adsorbents: Efficient removal of pollutants from wastewater

This study presents a novel approach to design and optimize a sodium alginate-based hydrogel (SAH) for efficient adsorption of the model water pollutant methylene blue (MB) dye. Utilizing density functional theory (DFT) calculations, sodium alginate-g-poly (acrylamide-co-itaconic acid) was identified with the lowest adsorption energy (Eads) for MB dye among 14 different clusters. SAHs were prepared using selected monomers and sodium alginate combinations through graft co-polymerization, and swelling studies were conducted to optimize grafting conditions. Advanced characterization techniques, including FTIR, XRD, XPS, SEM, EDS, and TGA, were employed, and the process was optimized using statistical and machine learning tools. Screening tests demonstrated that Eads serves as an effective predicting indicator for adsorption capacity (qe) and MB removal efficiency (RRMB,%), with reasonable agreement between Eads and both responses under given conditions. Process modeling and optimization revealed that 5 mg of selected SAH achieves a maximum qe of 3244 mg g-1 at 84.4% RRMB under pH 8.05, 98.8 min, and MB concentration of 383.3 mg L-1, as identified by the desirability function approach. Moreover, SAH effectively eliminated various contaminants from aqueous solutions, including sulfasalazine (SFZ) and dibenzothiophene (DBT). MB adsorption onto selected SAH was exothermic, spontaneous, and followed the pseudo-first-order and Langmuir-Freundlich isotherm models. The remarkable ability of SAH to adsorb MB is attributed to its well-designed structure predicted through DFT and optimal operational conditions achieved by AI-based parametric optimization. By integrating DFT-based computations and machine-learning tools, this study contributes to the efficient design of adsorbent materials and optimization of adsorption processes, also showcasing the potential of SAH as an efficient adsorbent for the abatement of aqueous pollution.

A graphene oxide based composite granule for methylene blue separation from aqueous solution: Adsorption, kinetics and thermodynamic studies

Graphene oxide and chitosan composite material using as a high-efficiency and low-cost granular adsorbent for methylene blue removal was fabricated via self-assembling method. The effects of pH value, contact time, initial concentration, adsorbent dose, temperature, and recyclic stability on the adsorption performance of methylene blue in aqueous solution were investigated in detail. Desorption process with the effects of solvents, contact time, and temperature were also conducted carefully in this study. The adsorption kinetics and adsorption isotherm of dye adsorption process showed that dye adsorption process was fitted to the pseudo-second-order kinetic model and the Freundlich adsorption isotherm, indicating a physical adsorption process with multilayer adsorption. The intra-particle diffusion model indicated that the dye adsorption by the granular adsorbent was strongly happened during the first 4 h. The thermodynamic study showed that the adsorption was a spontaneous and exothermic process and dye ions were condensed onto the surface of adsorbent. The maximum adsorption capacity of dye on the granular adsorbent was calculated as 951.35 mg/g and the adsorbent could maintain its adsorption performance after six cycles. In general, this study provided an efficient, cost-effective, and recyclable the granular adsorbent for dye separation from aqueous solution.

Real-time imaging of ipsilateral parathyroid glands by retrograde injection of methylene blue into the superior thyroid artery: a new intraoperative parathyroid protection method

BACKGROUND

Postoperative hypoparathyroidism caused by parathyroid injury is a problem faced by thyroid surgeons. The current technologies for parathyroid imaging all have some defects.

METHODS

Patients with differentiated thyroid carcinoma (DTC) who underwent unilateral thyroidectomy plus ipsilateral central lymph node dissection were recruited. We dissected the main trunk of the superior thyroid artery entering the thyroid gland and placed the venous indwelling tube into the artery. The sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) were calculated.

RESULTS

A total of 132 patients enrolled in this single-arm clinical trial, 105 of them completed retrograde catheterization via the superior artery. The sensitivity was 69.23 and 83.33% respectively. The specificity was 72.91 and 64.89%. The accuracy was 72.91 and 64.89%. The PPV was 85.71 and 81.08%. The NPV was 22.58 and 45.45%. There were no patients with allergic reactions to the methylene blue, or methylene blue toxicity.

CONCLUSIONS

Retrograde injection of methylene blue via the superior thyroid artery is an effective and safe method to visualize parathyroid glands. This method can accurately locate the target organ by ultraselecting the blood vessel and injecting the contrast agent while avoiding background contamination and reducing the amount of contrast agent.

TRIAL REGISTRATION

Clinical trial registration numbers and date of registration: ChiCTR2300077263、02/11/2023.

Cellulose acetate nanofiber modified with polydopamine polymerized MOFs for efficient removal of noxious organic dyes

The need to effectively remove toxic organic dyes from aquatic systems has become an increasingly critical issue in the recent years. In pursuit of this objective, polydopamine (PDA)-binary ZIF-8/UiO-66 (MOFs) was synthesized and incorporated into cellulose acetate (CA), producing ZIF-8/UiO-66/PDA@CA composite nanofibers under meticulously optimized conditions. The potential of fabricated nanofibers to remove cationic methylene blue (MB) dye was investigated. Various analysis tools including FTIR, XRD, SEM, zeta potential, BET, tensile strength testing, and XPS were employed. Results revealed a substantial leap in tensile strength, with ZIF-8/UiO-66/PDA@CA registering an impressive 2.8 MPa, as a marked improvement over the neat CA nanofibers (1.1 MPa). ZIF-8/UiO-66/PDA@CA nanofibers exhibit an outstanding adsorption capacity of 82 mg/g, notably outperforming the 22.4 mg/g capacity of neat CA nanofibers. In binary dye systems, these nanofibers exhibit a striking maximum adsorption capacity of 108 mg/g, establishing their eminence in addressing the complexities of wastewater treatment. Furthermore, the adsorption data fitted to the Langmuir isotherm, and the pseudo-second-order kinetic model. The fabricated nanofiber demonstrates good reproducibility and durability, consistently upholding its performance over five cycles. This suite of remarkable attributes collectively underscores its potential as a robust, durable, and highly promising solution for the effective and efficient removal of pernicious MB dye, in the context of both water quality improvement and environmental preservation.

3D-printed stereolithographic fluidic devices for automatic nonsupported microelectromembrane extraction and clean-up of wastewater samples

BACKGROUND

There is a quest of novel functional and reliable platforms for enhancing the efficiency of microextraction approaches in troublesome matrices, such as industrial wastewaters. 3D printing has been proven superb in the analytical field to act as the springboard of microscale extraction approaches.

RESULTS

In this work, low-force stereolithography (SL) was exploited for 3D printing and prototyping bespoke fluidic devices for accommodating nonsupported microelectromembrane extraction (μEME). The analytical performance of 3D-printed μEME devices with distinct cross-sections, including square, circle, and obround, and various channel dimensions was explored against that of commonly used circular polytetrafluoroethylene (PTFE) tubing in flow injection systems. A computer-controlled millifluidic system was harnessed for the (i) automatic liquid-handling of minute volumes of donor, acceptor, and organic phases at the low μL level that spanned from 3 to 44 μL in this work, (ii) formation of three-phase μEME, (iii) in-line extraction, (iv) flow-through optical detection of the acceptor phase, and (v) solvent removal and regeneration of the μEME device and fluidic lines. Using methylene blue (MB) as a model analyte, experimental results evinced that the 3D-printed channels with an obround cross-section (2.5 mm × 2.5 mm) were the most efficient in terms of absolute extraction recovery (59%), as compared to PTFE tubing of 2.5 mm inner diameter (27%). This is attributed to the distinctive convex interface of the organic phase (1-octanol), with a more pronounced laminar pattern, in 3D-printed SL methacrylate-based fluidic channels against that of PTFE tubing on account of the enhanced 1-octanol wettability and lower contact angles for the 3D-printed devices. The devices with obround channels were leveraged for the automatic μEME and in-line clean-up of MB in high matrix textile dyeing wastewater samples with relative recoveries ≥81%, RSD% ≤ 17.1% and LOD of 1.3 mg L-1. The 3D-printed nonsupported μEME device was proven superb for the analysis of wastewater samples with an elevated ionic strength (0.7 mol L-1 NaCl, 5000 mg L-1 Na2CO3, and 0.013 mol L-1 NaOH) with recorded electric currents below 12 μA.

NOVELTY

The coupling of 3D printing with nonsupported μEME in automatic flow-based systems is herein proposed for the first time and demonstrated for the clean-up of troublesome samples, such as wastewaters.

Fabrication and characterization of binary composite MgO/CuO nanostructures for the efficient photocatalytic ability to eliminate organic contaminants: A detailed spectroscopic analysis

Design and eco-friendly fabrication of affordable and sustainable materials for the treatment of wastewater consisting of dyes, antibiotics, and other harmful substances has always been demanding. Untreated wastewater being released from industries imposes serious threats to our ecosystem, seeking convenient approaches to diminish this alarming issue. Here in this work, we synthesized MgO/CuO nanocomposites from a plant extract of Ammi visnaga L. and then employed these nanocomposites for the treatment of organic dye (methylene blue). We characterized the synthesized nanocomposites by dynamic light scattering (DLS), zeta potential, scanning electron microscopy (SEM), atomic force microscopy (AFM), transmission electron microscopy (TEM), x-ray diffraction (XRD), and X-ray photoelectron microscopy (XPS). DLS presented information about the explicit size of nanocomposites, while the surface charge was examined by zeta potential. XRD provided detailed information about the crystalline behavior and the information regarding surface morphology and size was extracted by SEM, TEM, and AFM. Moreover, the fabricated nanocomposites were used as a photocatalyst in the treatment of methylene blue. The overall catalytic reaction took an hour to complete, and the value of percentage degradation was 98 %. Substantially, a detailed account of the kinetics, rate of reaction, and mechanism is also fostered in the context. The presented study can assist scientists and researchers around the world to reproduce the results and use them to apply them on a broader scale.

A critical review and bibliometric analysis of methylene blue adsorption using leaves

The rapid development of the industrial world causes wastewater containing dyes to continue to increase. Even in recent years, the food, textile, cosmetic, plastic, and printing industries have developed the use of dyes. Methylene blue (MB) is one of the cationic dyes widely used in dyeing silk, wood, and cotton because of its absorbency and good fastness to materials. The adsorption process is the best technique and preferred in removing dyes from wastewater due to excellent selectivity, high efficiency from high-quality treated effluent, flexibility in design, and simplicity. Therefore, there is a growing interest to identify low-cost alternative adsorbents that have reasonable adsorption efficiency, especially natural materials such as leaves. In this study, research on MB adsorption using leaves was analyzed using bibliometric analysis. Information of bibliometric is extracted from the Scopus database with the keyword "Methylene Blue", "Adsorption or Desorption", and "Leaves or leaf". The results showed that India, Desalination and Water Treatment, and SASTRA Deemed University were the country, journal, and institution that contributed the most publications on this topic. Therefore, it is expected that with the use of bibliometrics, the use of leaf-based MB adsorption processes in their potential for MB dye removal can be investigated especially for large-scale development.

Enhanced Fenton-like process over Z-scheme MoO3 surface decorated with Fe2O3 under visible light

Photocatalysts consisting of Z-scheme heterojunctions are commonly used in wastewater treatment due to their exceptional reactivity in photocatalysis and highly efficient visible-light utilization. In this work, Fe2O3-decorated MoO3 rods were synthesized through a two-step method and their photodegradation of methylene blue (MB) was evaluated. The Fe2O3/MoO3 rods were characterized by XRD, SEM, micro-Raman, XPS, UV-Vis DRS, and PL to investigate their structural, morphological, and optical properties. The results indicate that the photodegradation efficiency of Fe2O3/MoO3 improved through a reduction in the gap energy and persistence of a 1D hexagonal prism structure. The degradation rate of MB was enhanced from 31.7 to 91.5% after irradiation for 180 min owing to electron-hole separation and Fenton-like process. Formation of the OH radical is a key factor in the photodegradation reaction and with the addition of H2O2 the efficiency can further improve via a Fenton-like mechanism. Furthermore, the Z-scheme mechanism concurrently delineated. The Fe2O3/MoO3 rod composites were also found to retain high photocatalytic efficiency after being reused five times, which may be useful for future applications.

The impact of methylene blue in colorectal cancer: Systematic review and meta-analysis study

PURPOSE

In patients with colorectal cancer (CRC), the most important factor to decide the need of adjuvant chemotherapy is the histological lymph node (LN) evaluation. Our work aimed to give a broad view over the use of methylene blue and its consequences in the number of lymph node harvest.

METHODS

PUBMED, WEB OF SCIENCE and EMBASE databases were consulted, retrieving clinical trials, which mentioned the used of intra-arterial methylene blue in patients with colorectal cancer.

RESULTS

Eighteen clinical trials analyzing the use of intra-arterial methylene blue in specimens of colorectal cancer were selected. The articles show a statistical difference between the use of methylene blue and the classical dissection in both variable at study. The results of the statistical analysis of the lymph node harvest variable demonstrate a significant statistical difference between the group that received methylene blue injection and the group that underwent conventional dissection. There is a significant statistical difference between the experimental and control groups for the ideal lymph node harvest (lymph node harvest count greater than 12).

CONCLUSION

The use of intra-arterial methylene blue revealed a high potential for the quantification of lymph nodes, considering the increase of lymph node harvest and the higher percentage of cases with more than 12 lymph nodes count, albeit the high heterogeneity between the studies in terms of reported results. Future investigations with controlled double blinded studies obtaining better categorized results should be conducted in order to better evaluate this technique and compare it to the current paradigm.

Coreactant-free strong Ru(bpy)32+ ECL at ionic liquid modified electrode and its application in sensitive detection of glucose based on resonance energy transfer

In this work, we have realized the strong anodic ECL emission of Ru(bpy)32+ at ionic liquid (N-butylpyridinium tetrafluoroborate) modified electrode without additional coreactant. Methylene blue (MB) could accept the energy of Ru(bpy)32+ ECL to construct resonance energy transfer (ECL-RET) system, leading to the decrease of ECL signal. In the presence of glucose oxidase, hydrogen peroxide generated from the oxidation process of glucose could oxidize MB and block the ECL-RET route, resulting in the recovery of ECL signal. As a consequence, the designed sensor showed outstanding performance for "signal-on" detection of glucose in the concentration range of 10 μM to 1 mM, and the detection limit was determined as 1.75 μM. Importantly, this study revealed new roles of ILs in the fabrication of coreactant-free ECL sensing, which might open up a promising route for the potential design and implement in clinical analysis.

Electrocatalytic aptasensor for bacterial detection exploiting ferricyanide reduction by methylene blue on mixed PEG/aptamer monolayers

Pathogen-triggered infections are the most severe global threat to human health, and to provide their timely treatment and prevention, robust methods for rapid and reliable identification of pathogenic microorganisms are required. Here, we have developed a fast and inexpensive electrocatalytic aptamer assay enabling specific and ultrasensitive detection of E. coli. E. coli, a biomarker of environmental contamination and infections, was captured on the mixed aptamer/thiolated PEG self-assembled monolayers formed on electrochemically pre-treated gold screen-printed electrodes (SPE). Signals from aptamer - E. coli binding were amplified by electrocatalytic reduction of ferricyanide mediated by methylene blue (MB) adsorbed on bacterial and aptamer surfaces. PEG operated as an antifouling agent and inhibited direct (not MB-mediated) discharge of ferricyanide. The assay allowed from 10 to 1000 CFU mL-1E. coli detection in 30 min, with no interference from B. subtilis, in buffer and artificial urine samples. This electrocatalytic approach is fast, specific, sensitive, and can be used directly in in-field and point-of-care applications for analysis of bacteria in human environment.

Effective degradation of synthetic micropollutants and real textile wastewater via a visible light-activated persulfate system using novel spinach leaf-derived biochar

A novel biochar (BC), derived from spinach leaves, was utilized as an activator for persulfate (PS) in the degradation of methylene blue (MB) dye under visible light conditions. Thorough analyses were conducted to characterize the physical and chemical properties of the biochar. The (BC + light)/PS system exhibited superior MB degradation efficiency at 83.36%, surpassing the performance of (BC + light)/hydrogen peroxide and (BC + light)/peroxymonosulfate systems. The optimal conditions were ascertained through the implementation of response surface methodology. Moreover, the (BC + light)/PS system demonstrated notable degradation ratios of 90.82%, 81.88%, and 84.82% for bromothymol blue dye, paracetamol, and chlorpyrifos, respectively, under optimal conditions. The predominant reactive species responsible for MB degradation were identified as sulfate radicals. Notably, the proposed system consistently achieved high removal efficiencies of 99.02%, 96.97%, 94.94%, 92%, and 90.35% for MB in five consecutive runs. The applicability of the suggested system was further validated through its effectiveness in treating real textile wastewater, exhibiting a substantial MB removal efficiency of 98.31% and dissolved organic carbon mineralization of 87.49%.

The impact of methylene blue photosensitizer, aPDT and a calcium hydroxide-based paste on the physicochemical and mechanical characteristics of root canal dentin and the bonding interface of fiberglass posts

PURPOSE

To investigate the influence of methylene blue (MB)-mediated antimicrobial photodynamic therapy (aPDT) and calcium hydroxide (CH) medication on the mechanical characteristics, degree of conversion (DC), quantification, and volume of gaps at the adhesive interface of glass fiber posts (GFPs) luted to distinct thirds of root canal dentin. Additionally, the microhardness (MH), elastic modulus (Eit), morphology, and chemical structure of the intraradicular dentin were assessed.

MATERIALS AND METHODS

6 experimental groups were formed by sorting 102 bovine incisors. Canals receiving deionized water irrigation as a negative control; canals receiving deionized water irrigation and filled with CH as a positive control; groups treated with CH + MB at 50 and 100 mg/L without irradiation; and groups treated with CH + MB at 50 and 100 mg/L irradiated by red laser for 60 s (660 nm; 100 mW; 6.5 J; 72 J/cm2). MH, Eit, and DC properties were evaluated for both the resin cement layer and root dentin substrate (n = 8). Volume and quantification of gaps at the bonding interface (n = 6), and dentin morphology and chemical content were investigated (n = 3). Data were analyzed using a repeated-measures 2-way ANOVA followed by Tukey post hoc analysis (α = 0.05).

RESULTS

The distinct intraradicular thirds and treatment with MB-mediated aPDT, whether activated or not, in combination with CH, had a significant impact on the mechanical characteristics of the root dentin. This effect was also observed in the MH, Eit, DC, quantification, and volume of gaps at the luting interface (P < .05). In general, a higher concentration of MB, whether activated by a red laser or not, led to lower values in the mechanical properties of the root dentin, as well as in MH, Eit, and DC at the adhesive interface (P < .05). Additionally, these groups exhibited higher values for quantification and volume of gaps at the luting substrate (P < .05). Scanning electron micrographs and energy dispersive X-ray spectra showed qualitative similarity among all groups, except for the negative experimental control group.

CONCLUSIONS

MB-mediated aPDT at 50 mg/L, in combination with CH, demonstrated favorable physico-chemical and mechanical characteristics in intraradicular dentin, along with satisfactory mechanical features and the adhesive interface integrity for GFPs at all intraradicular depths.

CLINICAL SIGNIFICANCE

MB-mediated aPDT at a concentration of 50 mg/L combined to CH medication represents a suitable choice for photosensitization in the context of intracanal disinfection following the biomechanical procedure and prior to luting of intraradicular restorations.

In-situ synthesis of ZIF-8 on magnetic pineapple leaf biochar as an efficient and reusable adsorbent for methylene blue removal from wastewater

The presence of organic dyes in aquatic systems poses a significant threat to ecosystems and human well-being. Due to recycling challenges, traditional commercial activated carbon is not cost-effective. To address this, an imidazolate acid zeolite framework-8 (ZIF-8)-modified magnetic adsorbent (ZMPLB-800) was synthesized through the in-situ formation of ZIF-8 and subsequent carbonization at 800 °C, using magnetic pineapple leaf biochar (MPLB) as a carrier. The porous structure of ZMPLB-800 facilitates the rapid passage of dye molecules, enhancing adsorption performance. ZMPLB-800 exhibited remarkable adsorption capacity for methylene blue (MB) across a pH range of 3-13, with a maximum adsorption capacity of 455.98 mg g-1. Adsorption kinetics and thermodynamics followed the pseudo-second-order kinetic model and Langmuir isotherm model. Mechanisms of MB adsorption included pore filling, hydrogen bonding, electrostatic interactions, π-π interactions, and complexation through surface functional groups. Additionally, ZMPLB-800 demonstrated excellent regeneration performance, recording a removal efficiency exceeding 87% even after five adsorption/desorption cycles. This study provides a novel strategy for treating dye wastewater with MOF composites, laying the foundation for waste biomass utilization.

Exploring the synergistic effects of amoxicillin and methylene blue on unsaturated lipid structures: A study of Langmuir monolayers and giant unilamellar vesicles

The potentially toxic effects of emerging pollutant mixtures often deviate from the individual compound effects, presenting additive, synergistic, or agonistic interactions. This study delves into the complex world of emerging pollutants' mixtures, with a particular focus on their potential impact on unsaturated lipid DOPC (1,2-dioleoyl-sn-glycerol-3-phosphocholine) structured as both monolayers and bilayers, which are valuable tools for mimicking cell membranes. Specifically, we examine the effects of two common types of pollutants: antibiotics (amoxicillin) and dyes (methylene blue). Utilizing Langmuir monolayers, our research reveals a synergistic effect within the pollutant mixture, as evidenced by pressure-area isotherms and polarization-modulated infrared reflection absorption spectroscopy. We identify the specific chemical interactions contributing to this synergistic effect. Furthermore, through contrast phase microscopy experiments on giant unilamellar vesicles (bilayer system), we find that the individual pollutants and the mixture exhibit similar molecular effects on the bilayer, revealing that the molecular size is a key factor in the bilayer-mixture of pollutant interaction. This highlights the importance of considering molecular size in the interactions with bilayer systems. In summary, our research dissects the critical factors of chemical interactions and molecular size concerning the effects of pollutants on DOPC, serving as simplified models of cell membranes. This study underscores the significance of comprehending the molecular effects of emerging pollutants on human health and the development of models for exploring their intricate interactions with cell membranes.

Production of eco-friendly adsorbent of kaolin clay and cellulose extracted from peanut shells for removal of methylene blue and congo red removal dyes

This present work targets the production of an eco-friendly adsorbent (hereinafter KA/CEL) from kaolin clay functionalized with cellulose extract obtained from peanut shells. The adsorbents were used for decolorization of two different types of organic dyes (cationic: methylene blue, MB; anionic: Congo red, CR) from an aqueous environment. Several analytical methods, including Brunauer-Emmett-Teller (surface properties), Fourier Transforms infrared (functionality), scanning electron microscope, Energy dispersive X-Ray (morphology), and pHpzc test (surface charge), were used to attain the physicochemical characteristics of KA/CEL. The Box-Behnken Design (BBD) was applied to determine the crucial factors affecting adsorption performance. These included cellulose loading at 25 %, an adsorbent dose of 0.06 g, solution pH set at 10 for MB and 7 for CR, a temperature of 45 °C, and contact times of 12.5 min for MB and 20 min for CR dye. The adsorption data exhibited better agreement with the pseudo-second-order kinetic and Freundlich models. The Langmuir model estimated the monolayer capacity to be 291.5 mg/g for MB and 130.7 mg/g for CR at a temperature of 45 °C. This study's pivotal finding underscores the promising potential of KA/CEL as an effective adsorbent for treating wastewater contaminated with organic dyes.

Synergistic adsorption of methylene blue with carrageenan/hydrochar-derived activated carbon hydrogel composites: Insights and optimization strategies

The study explores the use of hydrochar-derived activated carbon (AC) to improve the adsorption capacity and mechanical properties of carrageenan (CAR) hydrogel beads. Four distinct samples, with carrageenan to activated carbon ratios of 1:0 (CAR), 2:1 (CAC2), 4:1 (CAC4), and 10:1 (CAC10), were prepared. These polymeric beads underwent comprehensive evaluation for their methylene blue (MB) adsorption capacity, gel content (GC), and swelling ratio (SR). Increasing activated carbon content up to 50 % of carrageenan mass significantly enhanced GC and SR by 20.57 % and 429.24 %, respectively. Various analytical techniques were employed to characterize the composites, including FTIR, XRD, Raman Spectroscopy, BET, SEM, and EDS-Mapping. Batch adsorption tests investigated the effects of pH, contact time, dye concentration, and temperature on MB adsorption. Maximum adsorption capacities for CAR, CAC10, CAC4, and CAC2 were 475.48, 558.54, 635.93, and 552.35 mg/g, respectively, under optimal conditions. Kinetic models (Elovich and pseudo-second-order) and isotherm models (Temkin for CAR and Freundlich for CAC10, CAC4, and CAC2) fitted well with the experimental data. Thermodynamic analysis showed spontaneous, exothermic MB adsorption. Primary mechanisms include electrostatic attraction, hydrogen bonding, n-π, and π-π stacking. The study highlights enhanced adsorption capacity of carrageenan hydrogel via carrageenan/activated carbon composites, providing cost-effective wastewater treatment.

Novel mint-stalks derived biochar for the adsorption of methylene blue dye: Effect of operating parameters, adsorption mechanism, kinetics, isotherms, and thermodynamics

The pyrolysis of mint stalks and lemon peels was performed to synthesize mint-stalks (MBC) and lemon-peels (LBC) derived biochars for adsorbing methylene blue (MB). The preparation, characterization, and application of MBC in adsorption have not been reported in the literature. MBC showed higher surface area and carbon content than that of LBC. The removal ratios of MB were 87.5% and 60% within 90 min for MBC and LBC, respectively at pH 7, temperature of 30oC, adsorbent dose of 0.5 g/L, and MB concentration of 5 mg/L. The optimal MBC dose was 1 g/L achieving a removal efficiency of 93.6% at pH 7, temperature of 30oC, contact time of 90 min, and initial dye concentration of 5.0 mg/L. The adsorption efficiency decreased from 98.6% to 31.33% by raising the dye concentration from 3.0 mg/L to 30 mg/L. Further, the increase of adsorbent dose to 10 g/L could achieve 94.2%, 90.3%, 87.6%, and 84.1% removal efficiencies of MB in the case of initial concentrations of 200 mg/L, 300 mg/L, 400 mg/L, and 500 mg/L, respectively. MBC showed high stability in adsorbing MB under five cycles, and the performed analyses after adsorption reaffirmed the stability of MBC. The adsorption mechanism indicated that the adsorption of MB molecules on the biochar's surface was mainly because of the electrostatic interaction, hydrogen bonding, and π-π stacking. Pseudo-second-order and Langmuir models could efficiently describe the adsorption of MB on the prepared biochar. The adsorption process is endothermic and spontaneous based on the adsorption thermodynamics. The proposed adsorption system is promising and can be implemented on a bigger scale. Moreover, the prepared biochar can be implemented in other applications such as photocatalysis, periodate, and persulfate activation-based advanced oxidation processes.

Alkaline protease based hydrothermal synthesis of novel Pd/CuO/ZnO nanocomposite: A new entry into photocatalytic and biomedical applications

Here, we reported the process for the production of Pd/CuO/ZnO nanocomposite utilizing alkaline protease from Phalaris minor seed extract, which is a unique, effective biogenic approach. Alkaline protease performed a crucial part in the reduction, capping and stabilization of Pd/CuO/ZnO nanocomposites. A series of physicochemical techniques were used to inquire the formation, size, shape and crystalline nature of Pd/CuO/ZnO nanocomposites. The notable performance of the synthesized nanocomposite as a photocatalyst and an antibacterial disinfectant was astonishing. The Pd/CuO/ZnO nanocrystals showed considerable photocatalytic activity by eliminating 99 % of the methylene blue (MB) in <30 min of exposure. After three test cycles, the nanocatalyst demonstrated exceptional reliability as a photocatalyst. The nanocomposite was also discovered to be an effective antibacterial agent, with zones of inhibitory activity for Staphylococcus aureus and Escherichia coli bacteria of 30(±0.2), 27(±0.3), 22(±0.2), and 21(±0.3) mm, respectively, in both light and dark conditions. Moreover, the Pd/CuO/ZnO nanocomposites showed strong antioxidant activity by efficiently scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals. The photocatalytic, antibacterial and antioxidative performance of Pd, CuO, ZnO, and CuO/ZnO were also assessed for the sake of comparison. This work shows that biogenic nanocomposites may be employed as a feasible alternative photocatalyst for the decomposition of dyes in waste water as well as a sustainable antibacterial agent.

Fabrication of date palm kernel biochar-sulfur (DPKB-S) for super adsorption of methylene blue dye from water

A novel form of biochar was created by dehydration of Date palm kernel with 85% sulfuric acid. It was examined how the newly produced biochar (DPKB-S) affected the aqueous solution's capacity to extract Methylene Blue (MB) dye. The prepared DPKB-S was categorized by BET, BJH, FT-IR, SEM, EDX, DSC, and TGA analyses. The ideal pH for the MB dye adsorption by DPKB-S is 8. With 0.75 g L-1 of DPKB-S and an initial concentration of 50 ppm MB dye, Date Palm Kernel Biochar-Sulfur (DPKB-S) had the highest removal percentage of 100%. The Langmuir and Freundlich isotherm models were used to investigate the collected data. Freundlich model is the model that best covers MB dye adsorption in DPKB-S at low concentrations (0.75-1.25 g L-1) and the Langmuir model at high concentrations (1.5-1.75 g L-1). The Langmuir model maximum adsorption capacity (Qm) of the DPKB-S was 1512.30 mg g-1. Furthermore, a variety of error function models were applied to investigate the isotherm models derived data, including Marquardt's percent standard deviation (MPSD), the sum of absolute errors (EABS), the sum of the errors squared (ERRSQ), root mean square errors (RMS), Chi-square error (X2), the average relative error (ARE), average percent errors (APE), and hybrid error function (HYBRID). Kinetic data were calculated by intraparticle diffusion (IPD), pseudo-second-order (PSO), pseudo-first-order (PFO), and film diffusion (FD) models. A PSO rate model with a strong correlation (R2 = 1.00) largely regulated the adsorption rate. The removal mechanism of MB dye by DPKB-S is based on the principle that these positively charged dyes are attracted by electrostatic attraction forces due to the growth in the number of negatively charged regions at basic pH value. According to the results, DPKB-S shows promise as an affordable and competent adsorbent for the adsorption of MB dye. It can be used frequently without experiencing a discernible decrease in adsorption efficiency.

The use of methylene blue to control the tumor oxygenation level

BACKGROUND

Hypoxia is a characteristic feature of many tumors. It promotes tumor proliferation, metastasis, and invasion and can reduce the effectiveness of many types of cancer treatment.

OBJECTIVE

The aim of this study was to investigate the pharmacokinetics of methylene blue (MB) and its impact on the tumor oxygenation level at mouse Lewis lung carcinoma (LLC) model using spectroscopic methods.

APPROACH

The pharmacokinetics of MB were studied qualitatively and quantitatively using video fluorescence imaging and fluorescence spectroscopy. The degree of hemoglobin oxygenation in vivo was examined by calculating hemoglobin optical absorption from the measured diffuse reflectance spectra. The distribution of MB fluorescence and the lifetime of NADH were analyzed using laser scanning microscopy and fluorescence lifetime imaging microscopy (FLIM) to assess cellular metabolism.

RESULTS

After intravenous administration of MB at 10-20 mg/kg, it quickly transitioned in the tumor to a colorless leucomethylene blue, with maximum accumulation in the tumor occurring after 5-10 min. A concentration of 10 mg/kg resulted in a relative increase of the tumor oxygenation level for small tumors (volume 50-75 mm3) and normal tissue 120 min after the introduction of MB. A shift in tumor metabolism towards oxidative phosphorylation (according to the lifetime of the NADH coenzyme) was measured using FLIM method after intravenous administration of 10 mg/kg of MB. Intravenous administration of MB at 20 mg/kg results in a long-term decrease in oxygenation, which persisted for at least 120 min after the administration and did not return to its initial level.

CONCLUSIONS

Administration of MB at 10 mg/kg shown to increase tumor oxygenation level, potentially leading to more effective antitumor therapy. However, at higher doses (20 mg/kg), MB may cause long-term decrease in oxygenation.

Interferon gamma (IFN-γ)-sensitive TB aptasensor based on novel chitosan-indium nano-kesterite (χtCITS)-labeled DNA aptamer hairpin technology

There has been increasing interest in the use of biosensors for diagnosis of infectious diseases such as tuberculosis (TB) due to their simplicity, affordability, and potential for point-of-care application. The incorporation of aptamer molecules and nanomaterials in biosensor fabrication explores the advantages of high-binding affinity and low immunogenicity of aptamers as well as the high surface-to-volume ratio of nanomaterials, for increased aptasensor performance. In this work, we employed a novel microwave-synthesized copper indium tin sulfide (CITS) substituted-kesterite nanomaterial, together with a natural biopolymer (chitosan), for signal amplification and increased loading of aptamer molecules. Study of the optical properties of CITS nanomaterials showed strong absorption in the UV region characteristic of kesterite semiconductor nanomaterials. X-ray diffraction analysis confirmed the presence of the kesterite phase with average crystallite size of 6.188 nm. Fabrication of interferon-gamma (IFN-γ) TB aptasensor with a chitosan-CITS nanocomposite (χtCITS) increased the aptasensor's electrochemical properties by 77.5 % and improved aptamer loading by 73.7 %. The aptasensor showed excellent sensitivity to IFN-γ concentrations with limit of detection of 6885 fg/mL (405 fM) and linear range of 850-17000 fg/mL (50 - 1000 fM). The aptasensor also exhibited excellent storage and electrochemical stability, with good selectivity towards IFN-γ and possible real sample application.

Functionalization of porous silica with graphene oxide and polyethyleneimine, containing zinc copper ferrite nanoparticles for water treatment and antibacterial application

The article discusses the removal of methylene blue (MB) dye, a common cationic dye used in the textile industry, from aqueous solutions through an adsorption process. The use of porous components as adsorbents are shown to facilitate complete separation after the process is completed. The substrate was synthesized by connecting zinc copper ferrite (ZnCuFe2O4), polyethyleneimine (PEI), and Graphene Oxide (GO) sheets to MCM-48, which is a mesoporous material. The surface of MCM-48 was modified using CPTMS, which created an O-Si-Cl bridge, thereby improving the adsorption rate. The substrate was shown to have suitable sites for electrostatic interactions and creating hydrogen bonds with MB. The adsorption process from the Freundlich isotherm (R2 = 0.9224) and the pseudo-second-order diagram (R2 = 0.9927) demonstrates the adsorption of several layers of dye on the heterogeneous surface of the substrate. The synthesized substrate was also shown to have good bactericidal activity against E. coli and S. aureus bacterial strain. Furthermore, the substrate maintained its initial ability to adsorb MB dye for four consecutive cycles. The research resulted that ZnCuFe2O4@MCM-48/PEI-GO substrate has the potential for efficient and economical removal of MB dye from aqueous solutions (R = 88.82%) (qmax = 294.1176 mg. g-1), making it a promising solution for the disposal of harmful industrial waste.

Synthesis of fluorescent carbon dots by B/P doping and application for Co2+ and methylene blue detection

During the synthesis of carbon dots, different heteroatom doping can change the fluorescence color and the emission wavelength when the same precursor is applied. In this study, we used o-phenylenediamine and L-lysine as raw materials, boric acid or phosphoric acid as different heteroatom dopants, and water as solvent to synthesize doped carbon dots through a simple microwave-assisted method. Finally, two kinds of doped carbon dots with different fluorescence colors under 365 nm UV light were obtained, of which the B-doped carbon dots (B-CDs) showed orange fluorescence, and the P-doped carbon dots (P-CDs) showed red fluorescence. Both carbon dots had satisfactory fluorescence quantum yields and can be used as fluorescence probes. Therefore, we investigated the detection performance of these two carbon dots when they were used as fluorescent probes. B-CDs can selectively detect Co2+ with a detection limit of 0.1102 μM, and at the same time, it can realize the naked eye detection of Co2+ in a certain concentration range. The P-CDs could sensitively detect methylene blue with a detection limit of 0.048 μM.

Curdlan/sodium carboxymethylcellulose composite adsorbents: A biodegradable solution for organic dye removal from water

Composite adsorbent comprised of curdlan (CURD) and sodium carboxymethylcellulose (CMC) were fabricated through a single-step heating process, targeting the removal of methylene blue (MB) from wastewater. The CURD/CMC composite adsorbents had a honeycomb porous structure. The integration of CMC not only increased the storage modulus of the CURD/CMC composite hydrogels but also affected the thermal stability and swelling behavior of the composite adsorbents in different pH solutions. Specifically, the addition of 1.2 % CMC increased the peak temperature (184.73 °C) of CURD/CMC composite adsorbent melting by 5.99 °C compared to CURD adsorbent. The addition of CMC improved the swelling ratio of the composite adsorbent at pH 3,7, and 12 with swelling ratio up to 918.07 %. The synergistic interaction between CURD and CMC led to an enhanced adsorption capacity of the aerogel for MB, achieving a maximum adsorption capability of 385.85 mg/g. Adsorption isotherm assessments further demonstrated that the Langmuir isotherm model well fitted the adsorption data of the composite adsorbent on MB. Collectively, these findings underscore the potential of the developed biodegradable adsorbents as promising adsorbents for efficiently eliminating organic dyes from water.

Two-dimensional heterojunction layered graphene oxide/graphitic carbon nitride photocatalyst for removal of toxic environmental dye methylene blue

The direct thermal polymerization techniques were applied to prepare the graphene oxide (GO)-graphitic carbon nitride (gCN) hybrid structure. The prepared hybrid heterojunction GO-gCN nanosheets were utilized as a photocatalyst to remove model pollutants methylene blue (MB) dye. The basic physio-chemical properties of GO-gCN layered materials have been analyzed by various characterization techniques. In addition, the proposed materials have a higher photocatalytic ability toward the degradation of aqueous solution of MB dye under visible light irradiation within a short treatment time. This is because it's the synergistic effects of GO-gCN layer-by-layer structures produced by π─π stacking with charge-transfer interactions. The gCN with GO composite can able to enhance the charge transfer and light-harvesting properties. Under the influence of photocatalyst, the surface of Graphene oxide undergoes the separation and combination of carbonyl radicals, hydroxyl radicals, epoxy radicals, and electron-hole pairs. This enhances the absorption of visible light and improves the degradation of MB, when GO is incorporated into gCN. The removal efficiency of MB reached up to 82.311% within the short treatment time.

Anatomic evaluation to compare the dye spread with ultrasound-guided pericapsular nerve group (PENG) injection with or without an additional suprainguinal fascia iliaca (SIFI) injection in soft embalmed cadavers

BACKGROUND

Novel interfascial plane blocks like PEricapsular Nerve Group (PENG) and SupraInguinal Fascia Iliaca (SIFI) blocks are effective for management of hip fracture pain. We compared the difference in the distribution of the dye injected and nerves stained by the addition of the SIFI block to the PENG block.

METHODS

A total of 24 designated dye injections were performed in eight soft-embalmed cadavers. Under ultrasound guidance 20 ml green ink injected bilaterally in PENG block and 30 ml methylene blue dye was injected in the SIFI block on the right side. The cadavers were dissected 24 h later to assess the extent of dye spread.

RESULTS

Extensive spread of dyes was seen on both side of iliacus muscle on the right side, but blue dye was not visible medial to the psoas tendon. The subcostal and iliohypogastric nerves were stained green in the infra-inguinal region. On the left side (PENG alone), the anterior division of the obturator, femoral and saphenous nerve (7/8) and iliohypogastric nerves (3/8) were stained in the infrainguinal region. In the suprainguinal region, the femoral nerve (5/8), accessory obturator nerve (3/8), lateral femoral cutaneous (1/8) and nerve to rectus femoris (4/8) were stained. The main obturator nerve trunk was spared with both injections while its anterior branch and accessory obturator nerve were stained with the PENG injection.

CONCLUSION

The study findings indicate that combined PENG + SIFI injections lead to an extensive craniocaudal and longitudinal spread along the iliacus muscle. We perceive that the combination of these two injections will have a superior clinical outcome.

An efficient eco-friendly adsorbent material based on waste copper slag-biomass ash geopolymer: dye sorption capacity and sustainable properties

The primary intent of the research is to comprehensively assess the environmental benefits and cost dynamics associated with the adsorption process of CS-RHA (Copper Slag and Rice Husk Ash) to produce a novel geopolymer adsorbent material for application in wastewater treatment. The geopolymer forms a polyiron sialate network under alkali activation by dissolving fayalite, and aluminium silicate to ferro-ferri silicate hydrate gel. The mechanical strength, leaching characteristics, and microstructure of the geopolymer were determined using XRD and FTIR, and magnetic properties by VSM as well surface properties were derived from BET surface area and zeta potential. Recognizing the critical role of sodium iron silicate hydrate (NFS) in the sorption of methylene blue (MB) dyestuff, batch experiments were carried out using different adsorbents. The results indicated that the dye removal efficiency increased from 60% in control samples (FS) to 98% for the blend (FS1) under different pH values. The data was found to fit with the nonlinear form of Freundlich isotherm and follow pseudo-second-order kinetics. The active adsorption sites were deduced as -O-Fe-O-Si-O-Na and Si-OH groups. The addition of RHA increases the adsorption capacity of the geopolymer in a short time through chemical adsorption. The significant negative surface charge promotes MB adsorption via improved electrostatic attraction. The spent adsorbents were recovered through magnetic separation with a retrieval rate of 80-85% and active sites were rejuvenated by calcination. Consequently, waste copper slag emerges as a promising adsorbent with minimum potential ecological risk and high effective recycling capacity.

A novel ZnCo2O4/BiOBr p-n/Z-scheme heterojunction photocatalyst for enhancing photocatalytic activity

In this study, we developed a novel p-n/Z-scheme heterojunction photocatalyst, ZnCo2O4/BiOBr (ZCo/BB), through a straightforward and safe hydrothermal-calcination-solvent thermal method. The composite photocatalyst demonstrated exceptional photocatalytic efficacy, particularly when the mass ratio of ZnCo2O4 was 25% (referred to as 25% ZCo/BB). Structural characterization and electrochemical analysis revealed that 25% ZCo/BB exhibited a larger specific surface area and a faster electron transfer rate. Under visible light exposure for 30 min, methylene blue (MB) degradation reached 92%, and the reaction rate constants were 8.2 and 3.7 times higher than those observed for individual ZnCo2O4 and BiOBr, respectively. Furthermore, the 25% ZCo/BB demonstrated exceptional photocatalytic stability over four cycles, maintaining over 80% MB degradation after each cycle. The outstanding photocatalytic activity was attributed to the p-n/Z-scheme heterojunction construction, which promoted charge separation and inhibited carrier recombination. In addition, ·OH and h+ were the major active species in photocatalysis, and · O 2 - was identified as a secondary active species. This work presents an efficient heterojunction photocatalyst for the degradation of organic wastewater.

Safety and feasibility comparison between three different CT-guided localization techniques under systemic approach algorithm

INTRODUCTION

In the era of lung cancer screening, more and more sub-centimeter indeterminate lung lesions are being identified. It is difficult to approach these lesions and obtain tissue to confirm diagnosis. CT-guided navigation followed by surgical resection is the best way to overcome this difficulty. The aim of this study is to compare the safety and feasibility of wire and dye-tattoo CT-guided localization techniques.

MATERIALS AND METHODS

From September 2019 to August 2021, 418 patients who presented with single lung lesion and received single CT-guided localization were included in this study. Procedure details, navigation results, and related complications were compared.

RESULTS

For patients who received wire localization, majority (98.3 %) had perihilar lesions. In addition, 68 (57.1 %) patients received tangential approach because of lesions were blocked by bony or vital structure, abutting major fissure, or previous approach failure. The characteristics of lesion location was quite different than dye-tattooing technique (p = 0.033). As regards persistence of the target lesion localization, the interval between localization and surgery using ICG tattooing was 829.0 ± 552.9 min; much longer than the other two navigation techniques (p < 0.0001). As regards safety, patients who received wire localization had a higher rate of pneumothorax (p = 0.042) and pulmonary hemorrhage (p < 0.001) than the dye-tattooing techniques.

DISCUSSION

CT-guided navigation techniques are safe and feasible. Wire localization is suitable for centrally located lesions but the wire needs to be fixed properly and symptomatic pneumothorax monitored for. Dye-tattooing is more suitable for peripheral lesions, while ICG localization persists longer than other techniques.

Defect-mediated time-efficient photocatalytic degradation of methylene blue and ciprofloxacin using tungsten-incorporated ternary perovskite BaSnO3 nanoparticles

Photocatalytic water purification has been extensively explored for its economic, eco-friendly, and sustainable aspects. In this study, tungsten (W) incorporated BaSn1-xWxO3 (x = 0 to 0.05) nanoparticles synthesized by facile hydrogen peroxide precipitation route has been demonstrated for photocatalytic degradation of methylene blue (MB) dye and ciprofloxacin (CIP) antibiotic. The structural analysis indicates the presence of hybrid composite-like nanostructures with reduced crystallinity. Optical studies reveal blueshift in bandgap and decrease in oxygen vacancy defects upon W-incorporation. Pure BaSnO3 shows overall enhanced photocatalytic activity towards MB (90.22%) and CIP (78.12%) after 240 min of white LED light and sunlight irradiation respectively. The 2 % W-incorporated BaSnO3 shows superior photocatalytic degradation of MB (26.89%) and CIP (45.14%) within first 30 min of irradiation confirming the presence of W to be beneficial in the process. The free radical study revealed the dominant role of reactive hole (h+) and oxygen radical (O2•-) species during photodegradation and their intermediates are investigated to elucidate the degradation mechanism of MB within 30 min of irradiation. This study is promising towards developing defect mediated and time-efficient photocatalysts for environmental remediation.

Selective adsorption of single and binary dyestuffs by citrus peel: Characterization, and adsorption performance

The powdered citrus peel, which has been replaced with sodium hydroxide, was used in this study to test how well methylene blue and reactive black 5 dyestuff absorbed one or both. To find out about the texture and surface chemistry of modified citrus peel, Fourier transform infrared spectroscopy and scanning electron microscope analyses were carried out. Fourier transform infrared spectroscopy data revealed the presence of amphoteric radicals on the modified citrus peel surface, indicating the effective adsorption of methylene blue and reactive black 5. Many parameters affecting the batch adsorption process, such as modified citrus peel dose (0.1-0.5 g), pH (2-10), time (20-80 min), stirring speed (60-180 rpm), and temperature (20-45 °C), were studied. It is seen that the physical effect is at the forefront, homogeneous monolayer adsorption occurs, and the process fits the Langmuir and pseudo first order models for dyestuffs. Thermodynamic modeling showed that the adsorption of methylene blue and reactive black 5 was spontaneous and endothermic. At pH 2, an adsorption capacity of 0.67 mg/g and a removal efficiency of 66.86% were achieved for reactive black 5. For methylene blue at pH 6, the adsorption capacity was 4.34 mg/g, and the decolorization rate was 87%. The decreases in the removal rates of dyestuffs in the binary system indicate that they are affected by their simultaneous presence in the solution. The results proved that modified citrus peel can be useful for dyestuff removal in single or binary systems, although the removal capacity of modified citrus peel is highly dependent on methylene blue and reactive black 5.

Facile construction of multifunctional xNiCo2O4/BiVO4 heterojunction with accelerated charge transfer for efficient photocatalytic treatment of Cr (VI), MB and TC under visible light

The release of industrial effluents, comprising of organic dyes, antibiotics, and heavy metals poses substantial environmental and ecological threats. Among the different approaches, the utilization of heterogeneous photocatalysis based on semiconducting metal oxides is of paramount important to removal of organic ( MB dye and TC antibiotic) and inorganic pollutants ( Cr (VI) ) in wastewater. In this work, a new approach for creating type-II heterojunction photocatalysts named xNiCo2O4/BiVO4 or BNC is suggested. The as-prepared samples were thoroughly examined by means of several sophisticated analytical tools to investigate their physicochemical properties. These composites were utilized in the decomposition of MB dye, TC drug and the reduction of Cr (VI) under visible light irradiation. According to the findings, the creation of type-II heterojunction at BiVO4-NiCo2O4 interface greatly improved charge transportation while successfully preventing electron-hole recombination. Among the various composites studied, BNC-2 demonstrated an enhanced photocatalytic activity towards degradation of MB and TC, which were found to be 91 % over a period of 150 min and 95 % within only 60 min, respectively. Moreover, the photocatalytic reduction of Cr (VI) was accomplished 96 % within just 25 min. Additionally, it is discovered that BNC-2 displayed promising photostability and recyclability with a retention of >90 % after five consecutive cycles. The enhanced photocatalytic activity of BNC-2 is evidently attributed to the expedited separation and transfer of charges, as proven by photocurrent measurement, photoluminescence and electrochemical impedance spectroscopy analyses. Hence, the current amalgamation of NiCo2O4 and BiVO4 heterojunction composite has paved novel paths towards photocatalytic removal of organic as well as inorganic contaminants.

Methylene blue as an adjuvant during cardiopulmonary resuscitation: an experimental study in rats

INTRODUCTION

Methylene Blue (MB) has been shown to attenuate oxidative, inflammatory, myocardial, and neurological lesions during ischemia-reperfusion and has great potential during cardiac arrest. This study aimed to determine the effects of MB combined with epinephrine during cardiac arrest on myocardial and cerebral lesions.

METHOD

Thirty-eight male Wistar rats were randomly assigned to four groups: the sham group (SH, n = 5), and three groups subjected to cardiac arrest (n = 11/group) and treated with EPI 20 µg.kg-1 (EPI), EPI 20 µg.kg-1 + MB 2 mg.kg-1 (EPI + MB), or saline 0.9% 0.2 ml (CTL). Ventricular fibrillation was induced by direct electrical stimulation in the right ventricle for 3 minutes, and anoxia was maintained for 5 minutes. Cardiopulmonary Resuscitation (CPR) consisted of medications, ventilation, chest compressions, and defibrillation. After returning to spontaneous circulation, animals were observed for four hours. Blood gas, troponin, oxidative stress, histology, and TUNEL staining measurements were analyzed. Groups were compared using generalized estimating equations.

RESULTS

No differences in the Returning of Spontaneous Circulation (ROSC) rate were observed among the groups (EPI: 63%, EPI + MB: 45%, CTL: 40%, p = 0.672). The mean arterial pressure immediately after ROSC was higher in the EPI+MB group than in the CTRL group (CTL: 30.5 [5.8], EPI: 63 [25.5], EPI+MB: 123 [31] mmHg, p = 0.007). Serum troponin levels were high in the CTL group (CTL: 130.1 [333.8], EPI: 3.70 [36.0], EPI + MB: 43.7 [116.31] ng/mL, p < 0.05).

CONCLUSION

The coadministration of MB and epinephrine failed to yield enhancements in cardiac or brain lesions in a rodent model of cardiac arrest.

Valorization of sugarcane bagasse with in situ grown MoS2 for continuous pollutant remediation and microbial decontamination

In this study, sugarcane bagasse (SB) was strategically subjected to a delignification process followed by the in situ growth of multi-layered molybdenum disulfide (MoS2) nanosheets with hexagonal phase (2H-phase) crystal structure via hydrothermal treatment. The MoS2 nanosheets underwent self-assembly to form nanoflower-like structures in the aligned cellulose inter-channels of delignified sugarcane bagasse (DSB), the mechanism of which was understood through FTIR and XPS spectroscopic studies. DSB, due to its porous morphology and abundant hydroxyl groups, shows remediation capabilities of methylene blue (MB) dye through physio-sorption but shows a low adsorption capacity of 80.21 mg/g. To improve the removal capacity, DSB after in situ growth of MoS2 (DSB-MoS2) shows enhanced dye degradation to 114.3 mg/g (in the dark) which further improved to 158.74 mg/g during photodegradation, due to catalytically active MoS2. Interestingly, DSB-MoS2 was capable of continuous dye degradation with recyclability for three cycles, reaching an efficiency of > 83%, along with a strong antibacterial response against Gram-positive Staphylococcus aureus (S.aureus) and Gram-negative Escherichia coli (E. coli). The present study introduces a unique strategy for the up-conversion of agricultural biomass into value-added bio-adsorbents, which can effectively and economically address the remediation of dyes with simultaneous microbial decontamination from polluted wastewater streams.

Investigating the synthesis parameters of durian skin-based activated carbon and the effects of silver nanocatalysts on its recyclability in methylene blue removal

Activated carbon (AC) is the most common and economically viable adsorbent for eliminating toxic organic pollutants, particularly dyes, from wastewater. Its widespread adoption is due to the simplicity and affordable production of AC, wherein low-cost agricultural wastes, such as durian skin can be used. Converting durian skin into AC presents a promising solution for its solid waste management. However, inherent drawbacks such as its non-selectivity, relatively short lifespan and laborious replacement and recovery processes diminish the overall efficacy of AC as an adsorbent. To address these challenges, the immobilisation of metal nanocatalysts such as silver nanoparticles (AgNPs) is one of the emerging solutions. AgNPs can facilitate the regeneration of the adsorption sites of AC by catalysing the conversion of the adsorbed dyes into harmless and simpler molecules. Nevertheless, the immobilisation of AgNPs on AC surface can be challenging as the pore size formation of AC is hard to control and the nanomaterials can easily leach out from the AC surface. Hence, in this study, we synthesised AC from durian skin (DS) and immobilised AgNPs on the AC-DS surface. Then, we used methylene blue (MB) removal for studying the adsorption capability and recyclability of the AC-DS. In the synthesis of AC-DS, the influences of reaction temperature, activating agent, and acid-washing to its capability in adsorptive removal of  MB in solution were first determined. It was found that 400 °C, KOH activating agent, and the presence of acid-washing (50% of HNO3) resulted in AC-DS with the highest percentage of MB removal (91.49 ± 2.86%). Then, the overall results from three recyclability experiments demonstrate that AC-DS with immobilised AgNPs exhibited higher MB removal after several cycles (up to 6 cycles) as compared to AC-DS alone, proving the benefit of AgNPs for the recyclability of AC-DS. We also found that AgNPs/Citrate@AC-DS exhibited better adsorption capability and recyclability as compared to AgNPs/PVP@AC-DS indicating significant influences of type of stabilisers in this study. This study also demonstrates that the presence of more oxygen-containing functional groups (i.e., carboxyl and hydroxyl functional groups) after acid-washing on AC-DS and in citrate molecules, has greater influence to the performance of AC-DS and AgNPs/Citrate@AC-DS in the removal of MB as compared to the influences of their BET surface area and pore structure. The findings in this study have the potential to promote and serve as a guideline for harnessing the advantages of nanomaterials, such as AgNPs, to enhance the properties of AC for environmental applications.

Antibacterial and photocatalytic potential of bioactive compounds extracted from freshwater microalgae species (Spirogyra and Ocillatoria): A comparative analysis

Water pollution by pathogenic bacteria and organic dyes poses potential health hazards for human and aquatic life. This study aims to explore the potential of bioactive compounds extracted from two microalgae species (Spirogyra and Ocillatoria) for water pollution control. The optimization of the extraction process for bioactive compounds resulted in the highest yield at 25 min for Spirogyra and 30 min for Ocillatotia species. Further, the extracted bioactive compounds were analyzed using Fourier transform infrared spectroscopy (FTIR) and gas chromatography-mass spectroscopy (GC-MS). The bioactive compounds exhibited significant antibacterial activity against gram-positive and gram-negative bacteria. Notably, Spirogyra species exhibited a higher zone of inhibition (19.5-20.7 mm) than Ocillatoria species (17.0-18.0 mm) against both gram-positive and gram-negative bacterial strains. Furthermore, the photocatalytic potential of these bioactive compounds was examined by assessing the photodegradation of methylene blue (MB) and crystal violet (CV) dyes under different light sources. The findings revealed that Spirogyra species exhibited better photocatalytic activity than Ocillatoria species for MB and CV. For MB, 89.75 %, 77.82 % and 63.54 % were photodegraded when exposed to UV light, sunlight and visible light using Spirogyra extract, compared to 84.90 %, 74.70 % and 58.30 % by Ocillatoria extract. Regarding CV, Spirogyra extract achieved photodegradation efficiency of 88.94 %, 76.59 % and 64.50 % under UV light, sunlight and visible light, higher than 83.60 %, 73.60 % and 57.70 % by Ocillatoria extract. Both Spirogyra and Ocillatoria species demonstrated the best performance for dye photodegradation under UV irradiation, demonstrating great potential for nature-based water treatment.

Silver-decorated SrTiO3 nanoparticles for high-performance supercapacitors and effective remediation of hazardous pollutants

SrTiO3/Ag nanocomposites were synthesized using a facile wet impregnation method, employing rigorous experimental techniques for comprehensive characterization. XRD, FTIR, UV, PL, FESEM, and HRTEM were meticulously utilized to elucidate their structural, functional, morphological, and optical properties. The electrochemical performance of the SrTiO3/Ag nanocomposite was rigorously assessed, revealing an impressive specific capacitance of 850 F/g at a current density of 1 A. Furthermore, the photocatalytic activity of the SrTiO3/Ag nanocomposite was rigorously examined using methylene blue (MB) dye, and the results were outstanding. After 120 min of UV irradiation, the nanocomposite exhibited an exceptional MB dye degradation efficiency exceeding 88%. The SrTiO3/Ag nanocomposite represents an exemplary catalyst in terms of efficiency, cost-effectiveness, environmental compatibility, and reusability. The electron and superoxide radicals play a chief role in the MB dye degradation process. The inclusion of Ag within the SrTiO3 matrix facilitated the formation of a conductive nano-network, ultimately resulting in superior capacitive and photocatalytic performance.

Hydrothermal synthesis and photocatalytic application of ZnS-Ag composites based on biomass-derived carbon aerogel for the visible light degradation of methylene blue

A facile and cost-effective hydrothermal followed by precipitation method is employed to synthesize visible light-driven ZnS-Ag ternary composites supported on carbon aerogel (CA). Extensive studies were conducted on the structural, morphological, and optical properties, confirming the successful formation of ternary nanocomposites. The obtained results evidently demonstrate the successful loading of ZnS and Ag onto the surface of the CA. High-resolution transmission electron microscopy analysis revealed that ZnS and Ag nanoparticles (AgNPs) were uniformly distributed on the surface of the CA with an average diameter of 18 nm. The biomass-derived CA, containing a hierarchical porous nano-architecture and an abundant number of -NH2 functional groups on the surface, can greatly prevent the agglomeration, stability and reduce particle size. Brunauer-Emmett-Teller analysis results indicated specific surface areas of 4.62 m2 g-1 for the CA, 48.50 m2 g-1 for the CA/ZnS composite, and 62.62 m2 g-1 for the CA/ZnS-Ag composite. These values demonstrate an increase in surface area upon the incorporation of ZnS and Ag into the CA matrix. Under visible light irradiation, the synthesized CA/ZnS-Ag composites displayed remarkably improved photodegradation efficiency of methylene blue (MB). Among the tested samples, the CA/ZnS-Ag composites exhibited the highest percentage of photodegradation efficiency, surpassing ZnS, CA, and CA/ZnS. The obtained percentages of degradation efficiency for CA, ZnS, CA/ZnS, and CA/ZnS-Ag composites were determined as 26.60%, 52.12%, 68.39%, and 98.64%, respectively. These results highlight the superior photocatalytic performance of the CA/ZnS-Ag composites in the degradation of MB under visible light conditions. The superior efficiency of the CA/ZnS-Ag composite can be attributed to multiple factors, including its elevated specific surface area, inhibition of electron-hole pair recombination, and enhanced photon absorption within the visible light spectrum. The CA/ZnS-Ag composites displayed consistent efficiency over multiple cycles, confirming their stable performance, reusability, and enduring durability, thereby showcasing the robust nature of this composite material.

Administration of methylene blue in septic shock: pros and cons

Septic shock typically requires the administration of vasopressors. Adrenergic agents remain the first choice, namely norepinephrine. However, their use to counteract life-threatening hypotension comes with potential adverse effects, so that non-adrenergic vasopressors may also be considered. The use of agents that act through different mechanisms may also provide an advantage. Nitric oxide (NO) is the main driver of the vasodilation that leads to hypotension in septic shock, so several agents have been tested to counteract its effects. The use of non-selective NO synthase inhibitors has been of questionable benefit. Methylene blue, an inhibitor of soluble guanylate cyclase, an important enzyme involved in the NO signaling pathway in the vascular smooth muscle cell, has also been proposed. However, more than 25 years since the first clinical evaluation of MB administration in septic shock, the safety and benefits of its use are still not fully established, and it should not be used routinely in clinical practice until further evidence of its efficacy is available.

Efficacy of methylene blue-mediated antimicrobial photodynamic therapy on clinical and radiographic outcomes among patients with periodontal diseases: A systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

This study aimed to assess the influence of methylene blue (MB)-mediated adjunctive antimicrobial photodynamic therapy (aPDT) when compared to conventional mechanical debridement (MD) alone on periodontal clinical and radiographic outcomes among periodontitis patients.

METHODS

Randomized clinical trials (RCTs) were incorporated by conducting an electronic search in Web of Science, Scopus, and PubMed for articles published in English up to August 2023 to address the following focused question based on the PICO format: "Whether the application of MB-mediated aPDT as an adjunctive to MD (Intervention) leads to improved periodontal clinical and/or radiographic outcomes (Outcome) among participants with and without periodontal diseases (Population) as compared to MD alone (Conparison)". The risk of bias (RoB) of the included studies was assessed using the modified Jadad scale. A meta-analysis was conducted, and it included the presentation of the standard mean difference (SMD) along with a 95 % confidence interval (CI).

RESULTS

In total, 11 studies were included in this systematic review and meta-analysis. The meta-analysis demonstrated statistically significant improvements in periodontal plaque index (SMD: -0.72 % [95 % CI: -0.99 % to -0.45 %]; p<0.00001), probing depth (SMD: -0.38 % [95 % CI: -0.57 % to -0.19 %; p<0.00001), and bleeding on probing (SMD: -0.44 % [95 % CI: -0.68 % to -0.20 %]; p = 0.0003) scores at the final follow-up visit after the application of MB-mediated aPDT in comparison with MD alone. Nevertheless, there was no statistically significant difference was observed in periodontal clinical attachment level values (SMD: -0.01 % [95 % CI: -0.21 % to 0.19 %]; p = 0.95) between the control group and the experimental group. Six studies achieved a low RoB, five were rated as having medium RoB, while no study received a high RoB.

CONCLUSION

MB-mediated aPDT, when used as an adjunct to conventional MD contributes to the improvement of periodontal clinical outcomes including PI, PD, and BOP in patients with periodontitis.

Low-cost and eco-friendly PVA/carrageenan membrane to efficiently remove cationic dyes from water: Isotherms, kinetics, thermodynamics, and regeneration study

Methylene blue (MB), a common dye in the textile industry, has a multitude of detrimental consequences on humans and the environment. Accordingly, it is necessary to remove dyes from water to guarantee our health and sustainable ecosystem. In this study, we developed polyvinyl alcohol (PVA)-based hydrogel adsorbents with high adsorption capacity by adding three types of carrageenan (kappa, iota, and lambda) to remove MB from water. Thanks to the functional groups, the PVA/carrageenan membranes dramatically increased the removal efficiency (kappa, 98.8%; iota, 97.0%; lambda, 95.4%) compared to the pure PVA membrane (6.3%). Among the three types of PVA/carrageenan membranes, the PVA/kappa-carrageenan membrane exhibited the best adsorption capacity of 147.8 mg/g. This result implies that steric hindrance was considerably significant, given that kappa carrageenan has only one sulfate group in the repeating unit, whereas iota and lambda carrageenan composite PVA membranes possess two and three sulfate groups. Apart from the maximum adsorption capacity, this study addressed a variety of characteristics of PVA/carrageenan membranes such as the effects of initial MB concentration, kappa carrageenan weight percentage, contact time, adsorbent dosage, and temperature on the adsorption performance. In addition, the kinetic and thermodynamic studies were also carried out. Lastly, the reusability of the PVA/carrageenan membrane was verified by the 98% removal efficiency maintained after five adsorption-desorption cycles.

In-situ preparation of lignin/Fe3O4 magnetic spheres as bifunctional material for the efficient removal of metal ions and methylene blue

In this paper, magnetic composite of lignin/Fe3O4 spheres were synthesized via a straightforward one-step in-situ solvothermal method showing good capacity for adsorbing heavy metal ions and dyes. The physicochemical properties of lignin/Fe3O4 spheres are analyzed using a range of techniques such as SEM, XRD, FTIR, VSM, TG, and BET. Lignin/Fe3O4 spheres exhibited high adsorption capacities of 100.00, 353.36 and 223.71 and 180.18 mg/g for Cu (II), Ni (II) and Cr (VI) metal ions and methylene blue (MB) with equilibrium attained within 60 min. After the recycling experiments, lignin/Fe3O4 spheres still possesses excellent superparamagnetic properties and displays high adsorption capacity. The lignin/Fe3O4 spheres are an efficient and continuous adsorbent to remove heavy metal ions of Cu (II), Ni (II), Cr (VI) and cationic dyes of methylene blue in wastewater, which proves the great potential in practical pollutants treatment applications for water systems.

Aging and characterization of disposable polypropylene plastic cups based microplastics and its adsorption for methylene blue

Microplastics (MPs) as emerging pollutants are of increasing concern, due to their ubiquitous, uncertain, and complex environmental impacts. Different from the standard spherical MPs without additives, here polypropylene microplastics (PP-MPs) in flake derived from the disposable plastic cup in food-grade in daily life were studied. The characterization of PP-MPs demonstrated that the carbonyl index represented the aging degree was enhanced from 0.26 significantly to 0.82 after 10 days, and the aging process fitted well with pseudo-first-order kinetic. Moreover, the crystallinity degree, polarity and surface negative charges were enhanced, while the hydrophobicity was decreased. The adsorption behavior of PP-MPs toward methylene blue (MB), and the impacts of various pHs, salinities, and humic acid in aquatic environments were also explored. The pseudo-second-order kinetic, Henry and Sips isotherm models provided a good correlation with the experimental data, indicating that the rate-limiting step was closely related with the complex surface adsorption, and the hydrophobic partitioning, polar interaction, electrostatic attraction, and hydrogen bonding were possibly involved in the adsorption. These exhaustive experiments aim to provide a theoretical basis for assessing and better understanding the environmental behavior of disposable PP plastic cups in nature.

Bioadsorbent nanocellulose aerogel efficiency impregnated with spent coffee grounds

Due to growing environmental concerns for better waste management, this study proposes developing a composite aerogel using cellulose nanofibers (CNF) and spent coffee grounds (SCG) through an eco-friendly method for efficient methylene blue (MB) adsorption. Adding SCG to the CNF aerogel altered the physical properties: it increases the volume (4.14 cm3 to 5.25 cm3) and density (0.018 to 0.022 g/cm3) but decrease the water adsorption capacity (2064 % to 1635 %). FTIR spectrum showed distinct functional groups in both all aerogels, showing hydroxyl, glyosidic bonds, and aromatic compounds. Additionally, SCG improved thermal stability of the aerogels. In term of adsorption efficacy, CNF-SCG40% aerogel as exceptionally well. According to Langmuir isotherm models, the adsorption of MB happened in a monolayer, with CNF-SCG40% showing a maximum adsorption capacity of 113.64 mg/g, surpassing CNF aerogel (58.82 mg/g). The study identified that the pseudo-second-order model effectively depicted the adsorption process, indicating a chemical-like interaction. This investigation successfully produced a single-use composite aerogel composed of CNF and SCG using an eco-friendly approach, efficiently adsorbing MB. By utilizing cost-effective materials and eco-friendly methods, this approach offers a sustainable solution for waste management, contributes to an eco-friendly industrial environment, and reduces production expenses and management costs.

aPDI meets PPE: photochemical decontamination in healthcare using methylene blue-where are we now, where will we go?

Personal protective equipment (PPE) reuse, first recommended in the context of the SARS-CoV-2 pandemic, can mitigate shortages in crisis situations and can greatly reduce the environmental impact of typically single-use PPE. Prior to safe reuse, PPE must be sanitized and contaminating pathogens-in current circumstances viruses in particular-must be inactivated. However, many established decontamination procedures are not equitable and remain unavailable in low-resource settings. In mid-2020, an interdisciplinary consortium of researchers first studied the potential of implementing cheap and easy-to-use antimicrobial photodynamic inactivation (aPDI) using methylene blue as photosensitizer to decontaminate face masks and filtering facepiece respirators. In this perspective piece, we describe the development of this novel method, discuss recent advances, and offer insights into how equitable PPE decontamination via methylene blue-based aPDI may be integrated into circular economy policies in the healthcare sector.

Effects of cation types in persulfate on physicochemical and adsorptive properties of biochar prepared from persulfate-pretreated bamboo

The adsorption behaviors of biochar are largely impacted by biomassfeedstock. In this study, two biochars were prepared from torrefaction of ammonium persulfate- and potassium persulfate-pretreated bamboo and then activated by cold alkali, which are named as ASBC and KSBC, respectively. The two biochars were characterized by different instruments, and their adsorption properties over cationic methylene blue (MB) were compared. The type of persulfates little affected the specific surface areas, but significantly impacted O (29.54 % vs. 35.113 %) and N (12.13 % vs. 3.74 %) contents, functional groups, and zeta potentials of biochars. MB adsorption onto ASBC/KSBC is a single-layer chemical endothermic process and ASBC/KSBC exhibit high adsorption capacity over MB (475/881 mg·g-1) at 303 K. Obviously, the sorption capacity of MB onto KSBC much surpasses that of MB onto ASBC. These results indicate biomass pre-treatment is a cheap and convenient method to prepare biochars with unique physicochemical and adsorptive properties.