Adsorption of doxorubicin hydrochloride on glutaric anhydride functionalized Fe3O4@SiO2 magnetic nanoparticles

Sulfonated Azocalix[4]arene-Modified Metal-Organic Framework Nanosheets for Doxorubicin Removal from Serum

Chemotherapy is one of the most commonly used methods for treating cancer, but its side effects severely limit its application and impair treatment effectiveness. Removing off-target chemotherapy drugs from the serum promptly through adsorption is the most direct approach to minimize their side effects. In this study, we synthesized a series of adsorption materials to remove the chemotherapy drug doxorubicin by modifying MOF nanosheets with sulfonated azocalix[4]arenes. The strong affinity of sulfonated azocalix[4]arenes for doxorubicin results in high adsorption strength (Langmuir adsorption constant = 2.45-5.73 L mg-1) and more complete removal of the drug. The extensive external surface area of the 2D nanosheets facilitates the exposure of a large number of accessible adsorption sites, which capture DOX molecules without internal diffusion, leading to a high adsorption rate (pseudo-second-order rate constant = 0.0058-0.0065 g mg-1 min-1). These adsorbents perform effectively in physiological environments and exhibit low cytotoxicity and good hemocompatibility. These features make them suitable for removing doxorubicin from serum during "drug capture" procedures. The optimal adsorbent can remove 91% of the clinical concentration of doxorubicin within 5 min.

Removal of doxorubicin hydrochloride and crystal violet from aqueous solutions using spray-dried niobium oxide coated with chitosan-activated carbon: Experimental and DFT calculations

Spray-dried niobium oxide coated with chitosan-activated carbon (NIC) was synthesized and used to remove doxorubicin hydrochloride and crystal violet from aqueous solutions under different parameters such as solution pH (2, 4, 6, and 8), contact time (1 to 9 h), initial concentration (20 to 200 mg L-1), and competing ions (0.1 M of CaCl2 and NaCl). The addition of 5 % chitosan-activated carbon to the matrix of niobium oxide slightly increased the specific surface area from 26 to 30 m2 g-1, with the introduction of a carboxylic functional group. This led to an increase in the amount of adsorbed doxorubicin hydrochloride (DOH) from 30 to 44 mg g-1 and that of crystal violet (CV) from 15 to 32 mg g-1 from the initial respective 100 mg L-1 at pH 8. The data from the concentration study fitted into Liu isotherm having adsorption capacity of 128 and 57 mg g-1 for DOH and CV respectively, while pseudo first and second order are more suitable for adsorption kinetics. The additional functional groups on the IR spectrum of NIC after the adsorption of DOH and CV confirmed the interaction between NIC and the adsorbates' molecules. The mechanism of adsorption was supported by DFT calculations.

Superior adsorption and removal of doxorubicin from aqueous solution using activated carbon via thermally treated green adsorbent: isothermal, kinetic, and thermodynamic studies

Activated carbon from apricot seeds (ASAC) was successfully made using a low-cost, straightforward synthesis process. With the use of various instruments, including XRD, XPS, FT-IR, SEM, and TEM, the adsorbent was demonstrated. The surface area of the ASAC that was given was also shown to be 436.8 m2/g. It was discovered that the synthesized ASAC has a fantastic capacity to absorb the anti-cancer medication doxorubicin hydrochloride (DOX). Based on changes in temperature, pH, and DOX concentration, The DOX adsorption behaviour's mechanism was evaluated. The adsorption capacity of ASAC for DOX was greater at pH 6.0, according to experimental data as the adsorption capacity was discovered to be 951.13 mg/g. Adsorption equilibrium analysis revealed that, when compared to the other models, the Langmuir adsorption provided the best fit to the data that were collected. Additionally, The ASAC has validated the DOX activation energy of adsorption as a chemisorption technique. The kinetics of adsorption were shown to be fitted to pseudo-second-order kinetic model. The reaction was endothermic and spontaneous, according to thermodynamic data. Innvestigation the removal efficiency of ASAC to remove DOX from real watrer sample (tap water, effluent wastewater, and impact wastewater). It was suggested by the results that ASAC was a viable option for treating wastewater and adsorbing DOX. The synthesized ASAC has noteworthy cyclability and reusability characteristics due to its high efficiency (up to five cycles) and low cost (around 86 percent).

Novel targeted delivery of quercetin for human hepatocellular carcinoma using starch/polyvinyl alcohol nanocarriers based hydrogel containing Fe2O3 nanoparticles

The common adverse effects of chemotherapy are the reason for the use of effective, natural drugs and targeted administration to specific areas. On the one hand, Quercetin (QC) has positive effects as a natural anticancer agent. On the other hand, Fe2O3, as nanoparticles (NP) with clinical properties and high porosity, can be a suitable carrier for drug loading and controlled release. In this study, QC was encapsulated in a synthesized Fe2O3/Starch/Polyvinyl alcohol nanocarrier (Fe2O3/S/PVA NC). Characterization of the NC was done by Fourier transforms infrared spectroscopy (FTIR), X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), vibrating sample magnetometer (VSM), zeta potential and Dynamic light scattering (DLS). The percentage of drug loading (DLE) and encapsulation efficiency (EE) of QC in the NC containing Fe2O3 nanoparticles was 47 % and 86.50 %, respectively, while it was 36 % and 73 % in the NC without Fe2O3. QC profile release in acidic and natural mediums showed controlled release and pH dependency of the NC. Viability of L929 and HepG2 treated cells with the Fe2O3/S/PVA/QC was demonstrated by MTT staining which was in agreement with flow cytometry. The results show that Fe2O3/S/PVA is a suitable NC for the targeted delivery of QC as a drug against HepG2 cancer cells.

Cr(VI) and doxorubicin adsorptive capture by a novel bionanocomposite of Ti-MOF@TiO2 incorporated with watermelon biochar and chitosan hydrogel

Biodegradable polymers, biochars and metal organic frameworks (MOFs) have manifested as top prospects for elimination of harmful pollutants. In the current study, Ti-MOF was synthesized and decorated with TiO2 nanoparticles, then embedded into watermelon peel biochar and functionalized with chitosan hydrogel to produce Ti-MOF@TiO2@WMPB@CTH. Various instruments were employed to assure the effective production of the bionanocomposite. The HR-TEM and SEM studies referred to excellent surface porosity and homogeneity of Ti-MOF@TiO2@WMPB@CTH bionanocomposite, with 51.02-74.23 nm. Based on the BET analysis, the mesoporous structure has a significant surface area of 366.04 m2 g-1 and a considerable total pore volume of 11.38 × 10-2 cm3 g-1, with a mean pore size of 12.434 nm. Removal of doxorubicin (DOX) and hexavalent chromium (Cr(VI)) was examined under various experimentations. Pseudo-second order kinetic models in addition to Langmuir isotherm offered the best fitting. Thermodynamic experiments of the two contaminants demonstrated spontaneous and endothermic interactions. After five subsequent adsorption and desorption cycles, Ti-MOF@TiO2@WMPB@CTH bionanocomposite demonstrated an exceptional recyclability for the elimination of DOX and Cr(VI) ions, reaching 97.96 % and 95.28 %, respectively. Finally, the newly designed Ti-MOF@TiO2@WMPB@CTH bionanocomposite demonstrated a high removing efficiency of Cr(VI) ions and DOX from samples of real water.

Effective Adsorption and Removal of Doxorubicin from Aqueous Solutions Using Mesostructured Silica Nanospheres: Box-Behnken Design Optimization and Adsorption Performance Evaluation

The aim of this study is to evaluate the efficacy of mesoporous silica nanospheres as an adsorbent to remove doxorubicin (DOX) from aqueous solution. The surface and structural properties of mesoporous silica nanospheres were investigated using BET, SEM, XRD, TEM, ζ potential, and point of zero charge analysis. To optimize DOX removal from aqueous solution, a Box-Behnken surface statistical design (BBD) with four times factors, four levels, and response surface modeling (RSM) was used. A high amount of adsorptivity from DOX (804.84 mg/g) was successfully done under the following conditions: mesoporous silica nanospheres dose = 0.02 g/25 mL; pH = 6; shaking speed = 200 rpm; and adsorption time = 100 min. The study of isotherms demonstrated how well the Langmuir equation and the experimental data matched. According to thermodynamic characteristics, the adsorption of DOX on mesoporous silica nanospheres was endothermic and spontaneous. The increase in solution temperature also aided in the removal of DOX. The kinetic study showed that the model suited the pseudo-second-order. The suggested adsorption method could recycle mesoporous silica nanospheres five times, with a modest reduction in its ability for adsorption. The most important feature of our adsorbent is that it can be recycled five times without losing its efficiency.

Optimal preparation of a core-shell structural magnetic nanoadsorbent for efficient tetracycline removal

As emerging contaminants, tetracyclines pose a severe threat to aquatic environments and human health. Therefore, developing efficient approaches to remove tetracyclines from water has attracted a large amount of interest. Herein, a novel core-shell structural magnetic nanoadsorbent (FSMAS) was facilely prepared by graft copolymerization of acrylamide (AM) and sodium p-styrene sulfonate (SSS) monomers on the surface of vinyl-modified Fe₃O₄@SiO₂ (FSM). From single factor experiments, the optimal graft copolymerization conditions were concluded to be the following: initiator concentration = 1.2‰, reaction pH = 9, monomer molar ratio = 7 : 3. The surface morphology, microstructure and physicochemical properties of as-prepared FSMAS were fully evaluated by different characterization techniques, including SEM, TEM, FTIR, XPS, XRD and VSM. The adsorption performance of FSMAS towards tetracycline hydrochloride (TCH) was systematically studied by batch adsorption experiments. Results showed that the adsorption capability of the adsorbent was largely enhanced after graft copolymerization. The removal rate of TCH by FSMAS reached 95% at solution pH = 4.0, almost 10 times higher than FSM. Besides, the adsorption process of TCH by FSMAS was very efficient, 75% of pollutant could be adsorbed after only 10 minutes, attributed to the stretch of polymer chains and the strong affinity provided by abundant functional groups. Furthermore, TCH-loaded FSMAS was easily regenerated with HCl solution, the regeneration rate was higher than 80% after five adsorption-desorption cycles. Superior adsorption capability, fast solid-liquid separation speed and satisfactory reusability demonstrated the great potential of FSMAS in practical tetracycline removal.

Core-shell micro/nanocapsules: from encapsulation to applications

Encapsulation is the way to wrap or coat one substance as a core inside another tiny substance known as a shell at micro and nano scale for protecting the active ingredients from the exterior environment. A lot of active substances, such as flavours, enzymes, drugs, pesticides, vitamins, in addition to catalysts being effectively encapsulated within capsules consisting of different natural as well as synthetic polymers comprising poly(methacrylate), poly(ethylene glycol), cellulose, poly(lactide), poly(styrene), gelatine, poly(lactide-co-glycolide)s, and acacia. The developed capsules release the enclosed substance conveniently and in time through numerous mechanisms, reliant on the ultimate use of final products. Such technology is important for several fields counting food, pharmaceutical, cosmetics, agriculture, and textile industries. The present review focuses on the most important and high-efficiency methods for manufacturing micro/nanocapsules and their several applications in our life.

pH-Responsible Doxorubicin-Loaded Fe3O4@CaCO3 Nanocomposites for Cancer Treatment

A magnetic nanocomposite (MNC) is an integrated nanoplatform that combines a set of functions of two types of materials. A successful combination can give rise to a completely new material with unique physical, chemical, and biological properties. The magnetic core of MNC provides the possibility of magnetic resonance or magnetic particle imaging, magnetic field-influenced targeted delivery, hyperthermia, and other outstanding applications. Recently, MNC gained attention for external magnetic field-guided specific delivery to cancer tissue. Further, drug loading enhancement, construction stability, and biocompatibility improvement may lead to high progress in the area. Herein, the novel method for nanoscale Fe3O4@CaCO3 composites synthesis was proposed. For the procedure, oleic acid-modified Fe3O4 nanoparticles were coated with porous CaCO3 using an ion coprecipitation technique. PEG-2000, Tween 20, and DMEM cell media was successfully used as a stabilization agent and template for Fe3O4@CaCO3 synthesis. Transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, and dynamic light scattering (DLS) data were used for the Fe3O4@CaCO3 MNC’s characterization. To improve the nanocomposite properties, the concentration of the magnetic core was varied, yielding optimal size, polydispersity, and aggregation ability. The resulting Fe3O4@CaCO3 had a size of 135 nm with narrow size distributions, which is suitable for biomedical applications. The stability experiment in various pH, cell media, and fetal bovine serum was also evaluated. The material showed low cytotoxicity and high biocompatibility. An excellent anticancer drug doxorubicin (DOX) loading of up to 1900 µg/mg (DOX/MNC) was demonstrated. The Fe3O4@CaCO3/DOX displayed high stability at neutral pH and efficient acid-responsive drug release. The series of DOX-loaded Fe3O4@CaCO3 MNCs indicated effective inhibition of Hela and MCF-7 cell lines, and the IC 50 values were calculated. Moreover, 1.5 μg of the DOX-loaded Fe3O4@CaCO3 nanocomposite is sufficient to inhibit 50% of Hela cells, which shows a high prospect for cancer treatment. The stability experiments for DOX-loaded Fe3O4@CaCO3 in human serum albumin solution indicated the drug release due to the formation of a protein corona. The presented experiment showed the “pitfalls” of DOX-loaded nanocomposites and provided step-by-step guidance on efficient, smart, anticancer nanoconstruction fabrication. Thus, the Fe3O4@CaCO3 nanoplatform exhibits good performance in the cancer treatment area.

Study on Doxorubicin Loading on Differently Functionalized Iron Oxide Nanoparticles: Implications for Controlled Drug-Delivery Application

Nanoplatforms applied for the loading of anticancer drugs is a cutting-edge approach for drug delivery to tumors and reduction of toxic effects on healthy cells. In this study, we describe the synthesis and compare the sorption properties of four types of potential doxorubicin-carriers, in which iron oxide nanoparticles (IONs) are functionalized with cationic (polyethylenimine, PEI), anionic (polystyrenesulfonate, PSS), and nonionic (dextran) polymers, as well as with porous carbon. The IONs are thoroughly characterized by X-ray diffraction, IR spectroscopy, high resolution TEM (HRTEM), SEM, magnetic susceptibility, and the zeta-potential measurements in the pH range of 3-10. The degree of doxorubicin loading at pH 7.4, as well as the degree of desorption at pH 5.0, distinctive to cancerous tumor environment, are measured. Particles modified with PEI were shown to exhibit the highest loading capacity, while the greatest release at pH 5 (up to 30%) occurs from the surface of magnetite decorated with PSS. Such a slow release of the drug would imply a prolonged tumor-inhibiting action on the affected tissue or organ. Assessment of the toxicity (using Neuro2A cell line) for PEI- and PSS-modified IONs showed no negative effect. In conclusion, the preliminary evaluation of the effects of IONs coated with PSS and PEI on the rate of blood clotting was carried out. The results obtained can be taken into account when developing new drug delivery platforms.

Fabricating of Fe3O4@Ag-MOF nanocomposite and evaluating its adsorption activity for removal of doxorubicin

The purpose of this research was to investigate the doxorubicin (DOX) adsorption behavior on Fe3O4@Ag-Metal Organic Framework (Fe₃O₄@Ag-MOF). This adsorbent was effectively prepared using a simple synthetic process. Many instruments, including FTIR, XRD, SEM, TEM, and XPS, were used to characterized the new Fe₃O₄@Ag-MOF. Additionally, the presented Fe₃O₄@Ag-surface MOF's area was shown to be 586.06 m2/g with a size of around 43 nm. The composite that was made has magnetic properties that were quite strong (63.3 emu/g). The produced Fe₃O₄@Ag-MOF was discovered to have a fantastic ability to adsorb the anti-cancer drug DOX, with a 1.72 mmol/g (934.85 mg/g) adsorption capacity. On the basis of changes in temperature, pH, and DOX concentration, the DOX adsorption behavior mechanism was investigated. The adsorption capacity of Fe₃O₄@Ag-MOF for DOX was greater at pH 7.0, according to experimental data. The adsorption equilibrium also demonstrated that the Langmuir adsorption was regulated the best fit to the extracted data compared with the other models. Additionally, the activation energy of adsorption for DOX onto Fe₃O₄@Ag-MOF was determined, indicating the chemisorption process. The adsorption kinetics was shown in the well-known kinetic model of the pseudo-second-order. The adsorption thermodynamic measurements were documented according to according to the enthalpy (ΔH°), entropy(ΔS°), and Gibbs free energy (ΔG°) parameters demonstrated that the reaction was endothermic and spontaneous thermodynamic. The adsorption of DOX onto Fe₃O₄@Ag-MOF from real water samples (tap water, effluent wastewater, and influence wastewater) were investigated. It's interesting that the synthetic adsorbent had great recyclability 72.6 percent in the fifth cycle indicating that it was highly recyclable. After adsorption, the typical Fe₃O₄@Ag-MOF XRD peak intensities and locations were mostly unchanged throughout adsorption indicates the crystalline phase remained steady. The results indicated that Fe₃O₄@Ag-MOF were a good candidate for adsorbing the DOX and treating wastewater.

Magnetic Ti3C2 MXene Nanomaterials for Doxorubicin Adsorption from Aqueous Solutions: Kinetic, Isotherms, and Thermodynamic Studies

In this work, the magnetic Ti₃C₂ MXene functionalized with β-cyclodextrin was prepared and characterized using scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectra, X-ray diffraction, X-ray photoelectron spectroscopy, vibrating sample magnetometry, and thermogravimetric analysis. The synthesized nanomaterial was used as an adsorbent to adsorb doxorubicin from aqueous solutions, and the experimental parameters that affected the adsorption efficiency were investigated. In addition, the adsorption characteristics including adsorption kinetics, adsorption isotherm, and thermodynamics were researched comprehensively. The adsorption kinetics of doxorubicin followed a pseudo-second-order kinetic model, which indicated that adsorption was the rate-limiting step, and the maximum adsorption capacity was 7.35 μg mg^-1 by shaking for 60 min at pH 7.0. The adsorption isotherm was well described using the Freundlich model, which implied that multilayer adsorption took place over the prepared nanomaterial for doxorubicin adsorption. The negative values of Gibbs free energy change (ΔG ⁰ < 0) demonstrated that doxorubicin adsorption was a spontaneous process. The positive values of entropy change (ΔS ⁰ > 0) implied that doxorubicin adsorption was an increasing random process. Enthalpy change values were positive (ΔH ⁰ > 0) and indicated that the adsorption of doxorubicin was endothermic. The adsorption percentage of doxorubicin remained in the range of 41.05-44.09%, and the relative standard deviation (RSD) based on the adsorption percentage through five replicate adsorption and desorption processes was 2.8%. These results indicated that the magnetic Ti₃C₂ MXene nanomaterials can be an effective adsorbent to adsorb DOX from aqueous solutions.

Synthesis of ferroferric oxide@silicon dioxide/cobalt-based zeolitic imidazole frameworks for the removal of doxorubicin hydrochloride from wastewater

Due to its low-cost, eco-friendliness and easy mode of separation biosynthesized magnetic ferroferric oxide (Fe₃O₄) can be successfully used for the removal of organic contaminants from wastewater. However, there are some challenges that to date have limited this compound's practical removal efficiency. Thus, in this study, a cobalt-based zeolitic imidazole frameworks (ZIF-67) coated biosynthesized ferroferric oxide@silicon dioxide (Fe₃O₄@SiO₂) magnetic composite (Fe₃O₄@SiO₂/ZIF-67) was prepared to address these issues and subsequently used to remove doxorubicin hydrochloride (DOX). Characterization results showed that the fabricated composite exhibited significant magnetic properties (16.1 emu·g^-1) with a size ranging between 50 and 250 nm. The amount of DOX adsorbed by the composite (90.7 mg·g^-1) was much higher than either of the component parts, which were only 35.7 and 82.5 mg·g^-1 for Fe₃O₄@SiO₂ and ZIF-67 respectively. This indicated enhanced DOX adsorption by Fe₃O₄@SiO₂/ZIF-67. The DOX adsorption best fit a pseudo-second order kinetic and Langmuir adsorption model. These studies suggested that the DOX adsorption mechanism involved a combination of electrostatic interactions, π-π stacking, hydrogen bonding and pore filling. Regeneration and application studies, exposing Fe₃O₄@SiO₂/ZIF-67 to real water samples, practically demonstrated that Fe₃O₄@SiO₂/ZIF-67 with propensity for magnetic separation and recycle is a promising nanomaterial for DOX removal.

High Drug Capacity Doxorubicin-Loaded Iron Oxide Nanocomposites for Cancer Therapy

Magnetic nanoparticles (MNPs) have great potential in the drug delivery area. Iron oxide (Fe3O4) MNPs have demonstrated a promising effect due to their ferrimagnetic properties, large surface area, stability, low cost, easy synthesis, and functionalization. Some coating procedures are required to improve stability, biocompatibility, and decrease toxicity for medical applications. Herein, the co-precipitation synthesis of iron oxide MNPs coated with four types of primary surfactants, polyethylene glycol 2000 (PEG 2000), oleic acid (OA), Tween 20 (Tw20), and Tween 80 (Tw80), were investigated. Dynamic light scattering (DLS), ζ-potential, and transmission electron microscopy (TEM) techniques were used for morphology, size, charge, and stability analysis. Methylene blue reactive oxygen species (ROS) detection assay and the toxicity experiment on the lung adenocarcinoma A549 cell line were conducted. Two loading conditions for anticancer drug doxorubicin (DOX) on MNPs were proposed. The first one provides high loading efficiency (~90%) with up to 870 μg/mg (DOX/MNPs) drug capacity. The second is perspective for extremely high capacity 1757 μg/mg with drug wasting (DOX loading efficiency ~24%). For the most perspective MNP_OA and MNP_OA_DOX in cell media, pH 7.4, 5, and 3, the stability experiments are also presented. MNP_OA_DOX shows DOX pH-dependent release in the acidic pH and effective inhibition of A549 cancer cell growth. The IC50 values were calculated as 1.13 ± 0.02 mM in terms of doxorubicin and 0.4 ± 0.03 µg/mL in terms of the amount of the nanoparticles. Considering this, the MNP_OA_DOX nano theranostics agent is a highly potential candidate for cancer treatment.

Magnetite graphene oxide modified with β-cyclodextrin as an effective adsorbent for the removal of methotrexate and doxorubicin hydrochloride from water

The purpose of this investigation was to analyze the performance of magnetite graphene oxide modified with β-cyclodextrin (GO@Fe₃O₄@β-CD) for adsorption of methotrexate (MTX) and doxorubicin (DOX) from aqueous solutions. Characterization of GO@Fe₃O₄@β-CD was carried out using some methods. The perfect conditions for the adsorption of MTX and DOX were 7.0, 45 min, 20 mg, and 25 °C for solution pH, contact time, adsorbent dose, and temperature, respectively, with removal efficiency values of 97.8% and 98.5% for MTX and DOX, respectively. The adsorption kinetic of MTX and DOX via GO@Fe₃O₄@β-CD followed pseudo second-order (PSO) model, while the adsorption isotherm obeyed Langmuir model by monolayer adsorption with maximum adsorption capacities of 198.5 and 204.5 mg g^-1 for MTX and DOX, respectively. Therefore, it could be argued that HCl and 0.1 mol L^-1 NaOH would reflect adequate elution properties for GO@Fe₃O₄@β-CD recovery.

In Vitro Study: Synthesis and Evaluation of Fe3O4/CQD Magnetic/Fluorescent Nanocomposites for Targeted Drug Delivery, MRI, and Cancer Cell Labeling Applications

In the present study, first, Fe₃O₄ nanoparticles were functionalized using glutaric acid and then composited with CQDs. Doxorubicin (DOX) drug was loaded to evaluate the performance of the nanocomposite for targeted drug delivery applications. The XRD pattern confirmed the presence of characteristic peaks of CQDs and Fe₃O₄. In the FTIR spectrum, the presence of carboxyl functional groups on Fe₃O₄/CQDs was observed; DOX (positive charge) is loaded onto Fe₃O₄/CQDs (negative charge) by electrostatic absorption. FESEM and AFM images showed that the particle sizes of Fe₃O₄ and CQDs were 23-75 and 1-3 nm, respectively. The hysteresis curves showed superparamagnetic properties for Fe₃O₄ and Fe₃O₄/CQDs (57.3 and 8.4 emu/g). The Fe₃O₄ hysteresis curve showed superparamagnetic properties (Ms and Mr: 57.3 emu/g and 1.46 emu/g. The loading efficiency and capacity for Fe₃O₄/CQDs were 93.90% and 37.2 mg DOX/g MNP, respectively. DOX release from Fe₃O₄/CQDs in PBS showed pH-dependent release behavior where after 70 h at pH 5 and 7.4, about 50 and 21% of DOX were released. Fluorescence images of Fe₃O₄/CQD-treated cells showed that Fe₃O₄/CQDs are capable of labeling MCF-7 and HFF cells. Also, T₂-weighted MRI scans of Fe₃O₄/CQDs in water exhibited high r₂ relaxivity (86.56 mM^-1 S^-1). MTT assay showed that DOX-loaded Fe₃O₄/CQDs are highly biocompatible in contact with HFF cells (viability = 95%), but they kill MCF-7 cancer cells (viability = 45%). Therefore, the synthesized nanocomposite can be used in MRI, targeted drug delivery, and cell labeling.

Adsorption, and controlled release of doxorubicin from cellulose acetate/polyurethane/multi-walled carbon nanotubes composite nanofibers

The cellulose acetate (CA)/poly (ε-caprolactone diol)/poly (tetramethylene ether) glycol-polyurethane (PCL-Diol/PTMG-PU)/multi-walled carbon nanotubes (MWCNTs) composite nanofibers were prepared via two-nozzle electrospinning on both counter sides of the collector. The performance of synthesized composite nanofibers was investigated as an environmental application and anticancer delivery system for the adsorption/release of doxorubicin (DOX). The synergic effect of MWCNTs and DOX incorporated into the nanofibers was investigated against LNCaP prostate cancer cells. The status of MWCNTs and DOX in composite nanofibers was demonstrated by SEM, FTIR and UV-vis determinations. The adsorption tests using nanofibrous adsorbent toward DOX sorption was evaluated under various DOX initial concentrations (100-2000 mg l^-1), adsorption times (5-120 min), and pH values (pH:2-9). Due to the fitting of isotherm and kinetic data with Redlich-Peterson and pseudo-second order models, both chemisorption and surface adsorption of DOX molecules mechanisms have been predicted. The drug release from both nanofibers and MWCNTs-loaded nanofibers was compared. The better drug sustained release profiles verified in the presence of composite nanofibers. LNCaP prostate cancer and L929 normal cells were treated to investigate the cytotoxicity and compatibility of synthesized composite nanofibers. The apoptosis/necrosis of hybrid nanofibers and MWCNTs loaded-nanofibers was investigated. The obtained results demonstrated the synergic effects of MWCNTs and DOX loaded-nanofibers on the LNCaP prostate cancer cells death.

Bimetallic Fe/Ni nanoparticles derived from green synthesis for the removal of arsenic (V) in mine wastewater

Since the incidences of arsenicosis have significantly increased worldwide in the last decade, remediation of arsenic (As) pollution is now imperative. In this study, calcined green synthesized Fe/Ni nanoparticles (C-Fe/Ni NPs) were evaluated for their efficacy for As (V) removal from aqueous solution. Under optimal experimental conditions As (V) removal efficiency reached 87.3%. Analysis of changes in the surface properties of C-Fe/Ni NPs before and after interaction with As (Ⅴ) using a range of advanced characterization techniques including IC-AFS, SEM-EDS, XPS and XRD revealed that the As removal mechanism involved only adsorption. Adsorption kinetics followed a pseudo-second order rate model (R² > 0.986) and adsorption best fit the Langmuir isotherm model (R² > 0.958). Thermodynamic studies indicated that adsorption was a spontaneous endothermic process. On the basis of these results, a removal mechanism of As (Ⅴ) by C-Fe/Ni NPs was proposed. Finally, the efficacy of the material for practical remediation of As from aqueous solution was assessed, including the influence of coexisting anions. While Cl^-, NO₃^- and SO₄^2- had little influence on As (V) removal, both H₂PO₄^- and HCO₃^- significantly negatively affected removal.

Ultra pH-sensitive nanocarrier based on Fe2O3/chitosan/montmorillonite for quercetin delivery

Harmful side effects of the chemotherapeutic agent have been investigated in many recent studies. Since Fe₂O₃ nanoparticles have proper porosity, they are capable for loading noticeable amount of drugs and controlled release. We developed Fe₂O₃/chitosan/montmorillonite nanocomposite. Quercetin (QC) nanoparticles, which have fewer side effects than chemical anti-tumor drugs, were encapsulated in the synthesized nanocarrier and were characterized by X-ray diffraction (XRD), Fourier transforms infrared spectroscopy (FTIR), field emission scanning electron microscopy (FE-SEM), vibrating sample magnetometer (VSM), dynamic light scattering (DLS), and zeta potential. For quercetin, the encapsulation efficiency and the loading efficiency of the drug in Fe₂O₃-CS-MMT@QC were found to be about 94% and 57%, respectively. The release profile of QC in different mediums indicated pH-dependency and controlled release of the nanocomposite, adhering to The Weibull kinetic model. Biocompatibility of the Fe₂O₃/CS/MMT nanoparticles against the MCF-7 cells was shown by MTT assay and confirmed by flow cytometry. These data demonstrate that the designed Fe₂O₃-CS-MMT@QC would have potential drug delivery to treat cancer cells.

Surface decorated magnetic nanoparticles with Mn-porphyrin as an effective catalyst for oxidation of sulfides

Mn-porphyrin complex was anchored coordinatively to silica-coated surface of magnetic nanoparticles (SMNP). Afterward, a heterogeneous nanocatalyst (Fe3O4@SiO2-MnTCPP) has been characterized by Fourier transform infrared (FT-IR), ultraviolet-visible (UV-vis) spectroscopy, powder X-ray diffraction (XRD), scanning electron microscopy (SEM), vibrating sample magnetometry (VSM), thermogravimetric analysis (TGA), and transmission electron microscope (TEM). A thermal stability up to around 350[Formula: see text]C was verified for prepared nanocatalyst based on thermogravimetric analysis. Finally, the catalytic performance of magnetically recoverable Mn-catalyst was exploited in the green oxidation of different sulfides with urea hydrogen peroxide (UHP) in the presence of imidazole as co-catalyst in ethanol under heterogeneous conditions. The eco-friendly property of ethanol strongly induced us to employ it as the reaction solvent in this oxidation system. Complete conversion ([Formula: see text]99) of sulfides to the corresponding sulfoxide or sulfones was obtained for ethyl phenyl sulfide, phenyl vinyl sulfide, diallyl sulfide, thiocyanatoethane, 2-ethyl mercaptoethanol and tetrahydrothiophene. Moreover, the recovered catalysts keep constant conversion yield up to at least three cycles.

Selective Adsorption of Aqueous Diclofenac Sodium, Naproxen Sodium, and Ibuprofen Using a Stable Fe3O4-FeBTC Metal-Organic Frameworka

The FeBTC metal–organic framework (MOF) incorporated with magnetite is proposed as a novel material to solve water contamination with last generation pollutants. The material was synthesized by in situ solvothermal methods, and Fe₃O₄ nanoparticles were added during FeBTC MOF synthesis and used in drug adsorption. X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and Raman spectroscopy characterized the materials, with N₂-physisorption at 77 K. Pseudo-second-order kinetic and Freundlich models were used to describe the adsorption process. The thermodynamic study revealed that the adsorption of three drugs was a feasible, spontaneous exothermic process. The incorporation of magnetite nanoparticles in the FeBTC increased the adsorption capacity of pristine FeBTC. The Fe₃O₄–FeBTC material showed a maximum adsorption capacity for diclofenac sodium (DCF), then by ibuprofen (IB), and to a lesser extent by naproxen sodium (NS). Additionally, hybridization of the FeBTC with magnetite nanoparticles reinforced the most vulnerable part of the MOF, increasing the stability of its thermal and aqueous media. The electrostatic interaction, H-bonding, and interactions in the open-metal sites played vital roles in the drug adsorption. The sites’ competition in the multicomponent mixture’s adsorption showed selective adsorption (DCF) and (NS). This work shows how superficial modification with a low-surface-area MOF can achieve significant adsorption results in water pollutants.

Can the properties of engineered nanoparticles be indicative of their functions and effects in plants?

The extensive applicability of engineered nanoparticles (ENPs) in various fields such as environment, agriculture, medicine or biotechnology has mostly been attributed to their better physicochemical properties as compared with conventional bulk materials. However, functions and biological effects of ENPs change across different scenarios which impede the progress in their risk assessment and safety management. This review thus intends to figure out whether properties of ENPs can be indicators of their behavior through summarizing and analyzing the available literature and knowledge. The studies have indicated that size, shape, solubility, specific surface area, surface charge and surface reactivity constitute a more accurate measure of ENPs functions and toxic effects in addition to mass concentration. Effects of ENPs are also highly dependent on dose metrics, species and strains of organisms, environmental conditions, exposure route and duration. Searching correlations between properties and functions or biological effects may serve as an effective way in understanding positive and negative impacts of ENPs. This will ensure safe design and sustainable future use of ENPs.

Synthesis of Fe3O4 nanoparticles @Trioctylmethylammonium thiosalicylat (TOMATS) as a new magnetic nanoadsorbent for adsorption of ciprofloxacin in aqueous solution

The aim of this research was to investigate ciprofloxacin (CIP) removal efficiency from aqueous solutions by using Fe3O4 nanoparticles @Trioctylmethylammonium thiosalicylat Ionic liquid (Fe3O4 NP@ TOMATS IL) as a new magnetic nanoadsorbent. The adsorbent was characterized by field emission scanning electron microscope-energy dispersive spectroscopy (FESEM-EDS), mapping, Fourier transform infrared spectroscopy (FT-IR), the Brunauer–Emmett–Teller (BET), X-ray powder diffraction (XRD). The effects of solution pH, adsorbent dose, contact time, initial CIP concentration, and temperature on CIP removal were also investigated. In optimal conditions such as pH = 5.6, CIP concentration = 30 mg/L, adsorbent dose = 0.15 g, temperature = 30 °C, contact time = 90 min, the removal efficiency in synthetic and real wastewater were obtained 87 and 73%, respectively. Batch experiments were carried out to study the sorption Kinetics, thermodynamics, and equilibrium isotherms of CIP with magnetic nanoadsorbent. The results show that all of the above factors influence CIP removal. The Langmuir adsorption isotherm fits the adsorption process well, with the pseudo second-order model describing the adsorption kinetics accurately. The thermodynamic parameters indicate that adsorption is mainly physical adsorption. Recycling experiments revealed that the behavior of adsorbent is maintained after recycling for four times.

Synthesis of magnetite/silica nanocomposites from natural sand to create a drug delivery vehicle

In this study, we report the synthesis of the magnetite/silica nanocomposites and their structural and functional groups, magnetic properties, morphology, antimicrobial activity, and drug delivery performance. The X-ray diffraction characterization showed that magnetite formed a spinel phase and that silica formed an amorphous phase. The particle sizes of magnetite increased from 8.2 to 13.2 nm with increasing silica content, and the particles were observed to be superparamagnetic. The nanocomposites tended to agglomerate based on the scanning electron microscopy images. The antimicrobial activity of the magnetite/silica nanocomposites revealed that the increasing silica content increased the inhibition zones by 74%, 77%, and 143% in case of Gram-positive bacteria (B. subtilis), Gram-negative bacteria (E. coli), and fungus (C. albicans), respectively. Furthermore, doxorubicin was used as the model compound in the drug loading and release study, and drug loading was directly proportional to the silica content. Thus, the increasing silica content increased the drug loading owing to the increasing number of OH- bonds in silica, resulting in strong bonds with doxorubicin. Based on this study, the magnetite/silica nanocomposites could be applied as drug delivery vehicles.

Modified green synthesis of Fe3O4@SiO2 nanoparticles for pH responsive drug release

A magnetic field activated drug delivery and pH-sensitive controlled drug release system based on carboxyl-modified green synthesized Fe₃O₄@SiO₂ (Fe₃O₄@SiO₂-Glu) nanoparticles was established. Doxorubicin hydrochloride (DOX), as a drug model, was adsorbed onto the Fe₃O₄@SiO₂-Glu nanoparticles' surface, where the observed drug loading capacity of 34.6 mg/g was attributed to electrostatic interaction between -COO^- on the surface of Fe₃O₄@SiO₂-Glu and -NH₃⁺ of DOX. The structure, morphology and physiochemical properties of Fe₃O₄@SiO₂-Glu were characterized via TEM, FTIR, XRD, N₂ adsorption/desorption isotherms, and Zeta potential measurements. The green synthesized Fe₃O₄@SiO₂-Glu nanoparticles exhibited multilayer architecture with a BET surface area of 79.9 m²/g and a magnetization saturation of 25.9 emu/g. Drug release experiments indicated that DOX was pH trigger released with 60.8% released within 72 h at pH 3.5. This system has important potential implications for the design of more effective and stable magnetic Fe₃O₄@SiO₂-Glu materials as drug carriers for targeted and controlled drug release.

Folic acid modified Fe3O4 nanoclusters by a one-step ultrasonic technique for drug delivery and MR imaging

Multifunctional nanoclusters based on Fe₃O₄ nanoparticles for magnetic resonance imaging (MRI) and drug delivery are reported here. At first, oleic acid (OA)-coated Fe₃O₄ nanoparticles were prepared. Then block copolymer Pluronic F127 or folic acid (FA) conjugated-Pluronic F127 was used to modify the hydrophobic nanoparticles to become hydrophilic Fe₃O₄@F127 nanoclusters via facile ultrasonic treatment. During this process, drug molecules can also be introduced into the nanoclusters and therefore the targeted drug delivery system was formed. Next, we verified the feasibility of the nanoclusters as drug delivery vehicles and magnetic contrast agents. The nanoclusters have an average size of 200 nm and remained stable in water for long periods. Folic acid-modified nanoclusters showed an enhanced intracellular uptake into HepG2 cells by using both cellular iron amount analysis and flow cytometry analysis. Besides, Fe₃O₄@F127@FA nanoclusters showed good compatibility in the tested concentration range and good sensitivity in T₂-weighted MRI. The magnetic nanoclusters combined with drug delivery properties have greatly increased the significance in the diagnosis and therapy of diseases, which are suitable for systematical administration of hydrophobic drugs and simultaneously MRI diagnosis.

Water-soluble Fe₃O₄@F127@FA nanoclusters were prepared by a facile ultrasonic-treated method for MR imaging and targeted drug delivery.

Magnetically recoverable porphyrin-based nanocatalysts for the effective oxidation of olefins with hydrogen peroxide: a comparative study

A simple method for the functionalization of magnetic nanoparticles, which is achieved by the attachment of metalloporphyrin onto the surface of amine functionalized silica-coated magnetic nanoparticles via an amide bond.

ZnO capped flower-like porous carbon-Fe3O4 composite as carrier for bi-triggered drug delivery

In this work, ZnO capped flower-like porous carbon-Fe₃O₄ composite (FPCS-Fe₃O₄-ZnO) was constructed as a carrier for pH and microwave bi-triggered drug delivery. In the composite, the FPCS achieves high-efficiency drug loading, the Fe₃O₄ acts as magnetic targeting agent and microwave absorption enhancer, and the ZnO nanoparticle as a sealing agent in response to pH stimulation. The carrier exhibited a flower-mesoporous sphere of 270 nm, a specific surface area of 101 m²/g, a saturation magnetization of 14.08 emu/g, as well as good microwave thermal conversion properties (The temperature was raised from 25 °C to 60 °C only 24 s). Simultaneously, the carrier achieved an efficient drug loading with a drug loading rate of 99.1%. During the drug release experiments, obvious pH-dependent release behavior was observed, the drug release rate at 12 h was 8.2%, 19.0%, and 56.3% at pH 7.4, 5.0 and 3.0 respectively. Moreover the drug release rate increased from 8.2% to 39.9% after microwave stimulation at pH 7.4. In addition, cytotoxicity tests indicate that the carrier has good biocompatibility. Thus, this multifunctional pH and microwave bi-triggered carrier was expected to be further applied to drug delivery system(DDS).

Decorated single-enantiomer phosphoramide-based silica/magnetic nanocomposites for direct enantioseparation

The nano-composites Fe₃O₄@SiO₂@PTA(+) and Fe₃O₄@SiO₂@PTA(−) (PTA: phosphoric triamide) were prepared and used for the chiral separation of five racemic mixtures.