Comprehensive Analysis of Contaminants in Powdered Milk Samples Using an HPGe for γ Radiation

Aims: This study aimed to assess the activity concentrations and cancer risk assessments of 232Th and 40K in powdered milk samples collected from various suppliers in Pakistan, considering the increasing concern about cancer risks associated with environmental radiological effects related to food consumption. Subjects and Methods: Specific activity concentrations were determined using a high-resolution, high-purity germanium γ-spectroscopy system. Results: The specific activity levels of 40K and 232Th in the analyzed powdered milk samples were found to be 230.86 and 6.87 Bq/kg, respectively, well within the safe limits recommended by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). The hazard index (0.074 Bq/kg) and radium equivalent (27.58 Bq/kg) were calculated as indicators of radiation hazard, along with absorbed dose (26.26 nGy/h), annual effective dose (0.13 nGy/h), and excess lifetime cancer risk (0.45). These parameters provide insights into the potential health risks associated with powdered milk consumption. Conclusions: The findings collectively affirm the radiological safety of the analyzed powdered milk samples, providing valuable insights into the potential health risks associated with their consumption.

Study loss of vegetative cover and increased land surface temperature through remote sensing strategies under the inter-annual climate variability in Jinhua-Quzhou basin, China

The Jinhua-Quzhou basin in China is one of the most susceptible areas to drought. Due to the loss of vegetation and great fluctuations in rainfall and surface temperature, global warming occurs. Timely, accurate, and effective drought monitoring is crucial for protecting local vegetation and determining which vegetation is most vulnerable to increased LST during the period 1982-2019. It assumes a strong correlation between loss of vegetation cover, changes in monsoon climate, drought, and increases in land surface temperature (LST). Due to significantly increased in LST, low precipitation and vegetation cover, NDVI, TVDI, VCI, and NAP are useful in characterizing drought mitigation strategies. The temperature vegetation drought index (TVDI), normalized difference vegetation index (NDVI), vegetation condition index (VCI), and monthly precipitation anomaly percentage (NAP) can be helped to characterize drought reduction strategies. Monthly NDVI, NAP, VCI, TVDI, normalized vegetation supply water index (NVSWI), temperature condition index (TCI), vegetation health index (VHI), and heat map analysis indicate that the Jinhua-Quzhou basin experienced drought during 1984, 1993, 2000, and 2011. Seasonal SR, WVP, WS, NDVI, VCI, and NAP charts confirm that the Jinhua-Quzhou basin was affected by severe drought in 1984, which continued and led to severe droughts in 1993, 2000, and 2011. Regression analysis showed a significant positive correlation between NDVI, TVDI, VCI, and NAP values, while NVSWI, TVDI, and VHI showed positive signs of good drought monitoring strategies. The research results confirm the correlation between loss of vegetation cover and LST, which is one of the causes of global warming. The distribution of drought changed a trend indicating that compared with the Jinhua region; the Quzhou region has more droughts. The changing trend of drought has characteristics from 1982 to 2019, and there are significant differences in drought changing trends between different Jinhua-Quzhou basin areas. Overall, from 1982 to 2019, the frequency of drought showed a downward trend. We believe that these results will provide useful tools for drought management plans and play a relevant role in mitigating the effects of drought and protecting humanity from climate hazards.

Regulation of hippo signaling mediated apoptosis by Rauvolfia tetraphylla in triple-negative breast cancer

Rauvolfia tetraphylla is an essential medicinal plant that has been widely used in traditional medicine for various disease treatments. However, the tumor suppressor activity of R. tetraphylla and its phytocompounds were not explored against triple-negative breast cancer. The current research investigated the impact of R. tetraphylla methanolic extract (RTE) and its isolated compounds Ajmaline (RTC1) and Reserpine (RTC2) on triple-negative breast cancer cell line (MDA-MB-231) focusing on anti-proliferative effects. Our study imparts that RTE and RTC2 showed promising cytotoxic effects compared to RTC1. So further experiments have proceeded with RTE and RTC2, to evaluate its proliferation, migration, and apoptotic effect. The result shows around 80% of cells were observed in the G0/G1 phase in cell cycle analysis indicating the cell cycle inhibition and duel staining clearly showed the apoptotic effect. The migration of cells after the scratch was 60.45% observed in control and 90% in treated cells showing the inhibition of migration. ROS distribution was intense compared to control indicating the increased ROS stress in treated cells. Both RTE and RTC2-treated cells showed the potential to suppress proliferation and induce apoptotic change by upregulating BAX and MST-1 and suppressing Bcl2, LATS-1, and YAP, proving that deregulation of YAP resulting in the blockage of TEAD-YAP complex and inhibit proliferation. Therefore, R. tetraphylla extract and its isolated compounds were demonstrated to find its ability to act against MDA-MB-231 and these findings will help adjudicate it as a therapeutic drug against experimental triple-negative breast cancer.

Zinc oxide nanoparticles functionalized with cinnamic acid for targeting dental pathogens receptor and modulating apoptotic genes in human oral epidermal carcinoma KB cells

BACKGROUND

Oral diseases are often attributed to dental pathogens such as S. aureus, S. mutans, E. faecalis, and C. albicans. In this research work, a novel approach was employed to combat these pathogens by preparing zinc oxide nanoparticles (ZnO NPs) capped with cinnamic acid (CA) plant compounds.

METHODS

The synthesized ZnO-CA NPs were characterized using SEM, FTIR, and XRD to validate their composition and structural features. The antioxidant activity of ZnO-CA NPs was confirmed using DPPH and ABTS free radical scavenging assays. The antimicrobial effects of ZnO-CA NPs were validated using a zone of inhibition assay against dental pathogens. Autodock tool was used to identify the interaction of cinnamic acid with dental pathogen receptors.

RESULTS

ZnO-CA NPs exhibited potent antioxidant activity in both DPPH and ABTS assays, suggesting their potential as powerful antioxidants. The minimal inhibitory concentration of ZnO-CA NPs against dental pathogens was found 25 µg/mL, indicating their effective antimicrobial properties. Further, ZnO-CA NPs showed better binding affinity and amino acid interaction with dental pathogen receptors. Also, the ZnO-CA NPs exhibited dose-dependent (5 µg/mL, 15 µg/mL, 25 µg/mL, and 50 µg/mL) anticancer activity against Human Oral Epidermal Carcinoma KB cells. The mechanism of action of apoptotic activity of ZnO-CA NPs on the KB cells was identified through the upregulation of BCL-2, BAX, and P53 genes.

CONCLUSIONS

This research establishes the potential utility of ZnO-CA NPs as a promising candidate for dental applications. The potent antioxidant, anticancer, and effective antimicrobial properties of ZnO-CA NPs make them a valuable option for combating dental pathogens.

The Role of Climate Change and Its Sensitivity on Long-Term Standardized Precipitation Evapotranspiration Index, Vegetation and Drought Changing Trends over East Asia

Droughts have become more severe and frequent due to global warming. In this context, it is widely accepted that for drought assessments, both water supply (rainfall) and demand (standardized precipitation evapotranspiration index, SPEI) should be considered. Using SPEI, we explored the spatial-temporal patterns of dry and wet annual and seasonal changes in five sub-regions of East Asia during 1902-2018. These factors are linked to excess drought frequency and severity on the regional scale, and their effect on vegetation remains an important topic for climate change studies. Our results show that the SPEI significantly improved extreme drought and mostly affected the SPEI-06 and SPEI-12 growing seasons in East Asia during 1981-2018. The dry and wet annual SPEI trends mostly affect the five sub-regions of East Asia. The annual SPEI had two extremely dry spells during 1936-1947 and 1978-2018. Japan, South Korea, and North Korea are wet in the summer compared to other regions of East Asia, with drought frequency occurring at 51.4%, respectively. The mean drought frequencies in China and Mongolia are 57.4% and 54.6%. China and Mongolia are the driest regions in East Asia due to high drought frequency and duration. The spatial seasonal analysis of solar radiation (SR), water vapor pressure (WVP), wind speed (WS), vegetation condition index (VCI), temperature condition index (TCI), and vegetation health index (VHI) have confirmed that the East Asia region suffered from maximum drought events. The seasonal variation of SPEI shows no clear drying trends during summer and autumn seasons. During the winter and spring seasons, there was a dry trend in East Asia region. During 1902-1990, a seasonal SPEI presented diverse characteristics, with clear wet trends in Japan, Mongolia, and North Korea in four different growing seasons, with dry trends in China and South Korea. During 1991-2018, seasonal SPEI presented clear dry trends in Japan, Mongolia, and North Korea in different growing seasons, while China and South Korea showed a wet trend during the spring, autumn, and winter seasons. This ecological and climatic mechanism provides a good basis for the assessment of vegetation and drought-change variations within East Asia. An understandings of long-term vegetation trends and the effects of rainfall and SPEI on droughts of varying severity is essential for water resource management and climate change adaptation. Based on the results, water resources will increase under global warming, which may alleviate the water scarcity issue in the East Asia region.

Solvothermal synthesis of VO2 nanoparticles with locally patched V2O5 surface layer and their morphology-dependent catalytic properties for the oxidation of alcohols

Vanadium oxides are promising oxidation catalysts because of their rich redox chemistry. We report the synthesis of VO2 nanocrystals with VO2(B) crystal structure. By varying the mixing ratio of the components of a binary ethanol/water mixture, different VO2 nanocrystal morphologies (nanorods, -urchins, and -sheets) could be made selectively in pure form. Polydisperse VO2(B) nanorods with lengths between 150 nm and a few micrometers were formed at large water : ethanol ratios between 4 : 1 and 3 : 2. At a water : ethanol ratio of 1 : 9 VO2 nanosheets with diameters of ∼50-70 nm were formed, which aggregated to nano-urchins with diameters of ∼200 nm in pure ethanol. The catalytic activity of VO2 nanocrystals for the oxidation of alcohols was studied as a function of nanocrystal morphology. VO2 nanocrystals with all morphologies were catalytically active. The activity for the oxidation of benzyl alcohol to benzaldehyde was about 30% higher than that for the oxidation of furfuryl alcohol to furfural. This is due to the substrate structure. The oxidation activity of VO2 nanostructures decreases in the order of nanourchins > nanosheets > nanorods.

Green, Solvent-Free Mechanochemical Synthesis of Nano Ag2O/MnO2/N-Doped Graphene Nanocomposites: An Efficient Catalyst for Additive-Base-Free Aerial Oxidation of Various Kinds of Alcohols

Herein, we report a solvent-less, straightforward, and facile mechanochemical technique to synthesize nanocomposites of Ag2O nanoparticles-doped MnO2, which is further codoped with nitrogen-doped graphene (N-DG) [i.e., (X %)N-DG/MnO2-(1% Ag2O)] using physical milling of separately prepared N-DG and Ag2O NPs-MnO2 annealed at 400 °C over an eco-friendly ball-mill process. To assess the efficiency in terms of catalytic performance of the nanocomposites, selective oxidation of benzyl alcohol (BlOH) to benzaldehyde (BlCHO) is selected as a substrate model with an eco-friendly oxidizing agent (O2 molecule) and without any requirements for the addition of any harmful additives or bases. Various nanocomposites were prepared by varying the amount of N-DG in the composite, and the results obtained highlighted the function of N-DG in the catalyst system when they are compared with the catalyst MnO2-(1% Ag2O) [i.e., undoped catalyst] and MnO2-(1% Ag2O) codoped with different graphene dopants such as GRO and H-RG for alcohol oxidation transformation. The effects of various catalytic factors are systematically evaluated to optimize reaction conditions. The N-DG/MnO2-(1% Ag2O) catalyst exhibits premium specific activity (16.0 mmol/h/g) with 100% BlOH conversion and <99.9% BlCHO selectivity within a very short interval. The mechanochemically prepared N-DG-based nanocomposite displayed higher catalytic efficacy than that of the MnO2-(1% Ag2O) catalyst without the graphene dopant, which is N-DG in this study. A wide array of aromatic, heterocyclic, allylic, primary, secondary, and aliphatic alcohols have been selectively converted to respective ketones and aldehydes with full convertibility without further oxidation to acids over N-DG/MnO2-(1% Ag2O). Interestingly, it is also found that the N-DG/MnO2-(1% Ag2O) can be efficiently reused up to six times without a noteworthy decline in its effectiveness. The prepared nanocomposites were characterized using various analytical, microscopic, and spectroscopic techniques such as X-ray diffraction, thermogravimetric analysis, Fourier-transform infrared spectroscopy, Raman, field emission scanning electron microscopy, and Brunauer-Emmett-Teller.

Marine-derived κ-carrageenan-coated zinc oxide nanoparticles for targeted drug delivery and apoptosis induction in oral cancer

BACKGROUND

Kappaphycus alvarezii, a marine red algae species, has gained significant attention in recent years due to its versatile bioactive compounds. Among these, κ-carrageenan (CR), a sulfated polysaccharide, exhibits remarkable antimicrobial properties. This study emphasizes the synergism attained by functionalizing zinc oxide nanoparticles (ZnO NPs) with CR, thereby enhancing its antimicrobial efficacy and target specificity against dental pathogens.

METHODS

In this study, we synthesized ZnO-CR NPs and characterized them using SEM, FTIR, and XRD techniques to authenticate their composition and structural attributes. Moreover, our investigation revealed that ZnO-CR NPs possess better free radical scavenging capabilities, as evidenced by their effective activity in the DPPH and ABTS assay.

RESULTS

The antimicrobial properties of ZnO-CR NPs were systematically assessed using a zone of inhibition assay against dental pathogens of S. aureus, S. mutans, E. faecalis, and C. albicans, demonstrating their substantial inhibitory effects at a minimal concentration of 50 μg/mL. We elucidated the interaction between CR and the receptors of dental pathogens to further understand their mechanism of action. The ZnO-CR NPs demonstrated a dose-dependent anticancer effect at concentrations of 5 μg/mL, 25 μg/mL, 50 μg/mL, and 100 μg/mL on KB cells, a type of Human Oral Epidermal Carcinoma. The mechanism by which ZnO-CA NPs induced apoptosis in KB cells was determined by observing an increase in the expression of the BCL-2, BAX, and P53 genes.

CONCLUSION

Our findings unveil the promising potential of ZnO-CR NPs as a candidate with significant utility in dental applications. The demonstrated biocompatibility, potent antioxidant and antiapoptotic activity, along with impressive antimicrobial efficacy position these NPs as a valuable resource in the ongoing fight against dental pathogens and oral cancer.

Sb-Doped Cerium Molybdate: An Emerging Material as Dielectric and Photocatalyst for the Removal of Diclofenac Potassium from Aqueous Media

This work reports the influence of antimony substitution in a cerium molybdate lattice for improved dielectric and photocatalytic properties. For this purpose, a series of Ce2-xSbx(MoO4)3 (x = 0.00, 0.01, 0.03, 0.05, 0.07, and 0.09) were synthesized through a co-precipitation route. The as-synthesized materials were characterized for their optical properties, functional groups, chemical oxidation states, structural phases, surface properties, and dielectric characteristics using UV-Vis spectroscopy (UV-Vis), Fourier transform infrared (FTIR) and Raman spectroscopies, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) analysis, and impedance spectroscopy, respectively. UV-Vis study showed a prominent red shift of absorption maxima and a continuous decrease in band gap (3.35 eV to 2.79 eV) by increasing the dopant concentration. The presence of Ce-O and Mo-O-Mo bonds, detected via FTIR and Raman spectroscopies, are confirmed, indicating the successful synthesis of the desired material. The monoclinic phase was dominant in all materials, and the crystallite size was decreased from 40.29 nm to 29.09 nm by increasing the Sb content. A significant increase in the dielectric constant (ε' = 2.856 × 108, 20 Hz) and a decrease in the loss tan (tanδ = 1.647, 20 Hz) were exhibited as functions of the increasing Sb concentration. Furthermore, the photocatalytic efficiency of pristine cerium molybdate was also increased by 1.24 times against diclofenac potassium by incorporating Sb (x = 0.09) in the cerium molybdate. The photocatalytic efficiency of 85.8% was achieved within 180 min of UV light exposure at optimized conditions. The photocatalytic reaction followed pseudo-first-order kinetics with an apparent rate constant of 0.0105 min-1, and the photocatalyst was recyclable with good photocatalytic activity even after five successive runs. Overall, the as-synthesized Sb-doped cerium molybdate material has proven to be a promising candidate for charge storage devices and a sustainable photocatalyst for wastewater treatment.

Morphology Controlled Deposition of Vanadium Oxide (VOx) Nanoparticles on the Surface of Highly Reduced Graphene Oxide for the Photocatalytic Degradation of Hazardous Organic Dyes

Semiconducting nanomaterials based heterogeneous photocatalysis represent a low-cost, versatile technique for environmental remediation, including pollution mitigation, energy management and other environmental aspects. Herein, we demonstrate the syntheses of various heterogeneous photocatalysts based on highly reduced graphene oxide (HRG) and vanadium oxide (VOx)-based nanocomposites (HRG-VOx). Different shapes (rod, sheet and urchin forms) of VOx nanoparticles were successfully fabricated on the surface of HRG under solvo-/hydrothermal conditions by varying the amount of water and ethanol. The high concentration of water in the mixture resulted in the formation of rod-shaped VOx nanoparticles, whereas increasing the amount of ethanol led to the production of VOx sheets. The solvothermal condition using pure ethanol as solvent produced VOx nano-urchins on the surface of HRG. The as-prepared hybrid materials were characterized using various spectroscopic and microscopic techniques, including X-ray diffraction, UV-vis, FTIR, SEM and TEM analyses. The photocatalytic activities of different HRG-VOx nanocomposites were investigated for the photodegradation of methylene blue (MB) and methyl orange (MO). The experimental data revealed that all HRG-VOx composite-based photocatalysts demonstrated excellent performance toward the photocatalytic degradation of the organic dyes. Among all photocatalysts studied, the HRG-VOx nanocomposite consisting of urchin-shaped VOx nanoparticles (HRG-VOx-U) demonstrated superior photocatalytic properties towards the degradation of dyes.

CBPDdb: a curated database of compounds derived from Coumarin-Benzothiazole-Pyrazole

The present article describes the building of a small-molecule web server, CBPDdb, employing R-shiny. For the generation of the web server, three compounds were chosen, namely coumarin, benzothiazole and pyrazole, and their derivatives were curated from the literature. The two-dimensional (2D) structures were drawn using ChemDraw, and the .sdf file was created employing Discovery Studio Visualizer v2017. These compounds were read on the R-shiny app using ChemmineR, and the dataframe consisting of a total of 1146 compounds was generated and manipulated employing the dplyr package. The web server is provided with JSME 2D sketcher. The descriptors of the compounds are obtained using propOB with a filter. The users can download the filtered data in the .csv and .sdf formats, and the entire dataset of a compound can be downloaded in .sdf format. This web server facilitates the researchers to screen plausible inhibitors for different diseases. Additionally, the method used in building the web server can be adapted for developing other small-molecule databases (web servers) in RStudio. Database URL: https://srampogu.shinyapps.io/CBPDdb_Revised/.

Synthesis and Structural Characterization of Selenium Nanoparticles-Bacillus sp. MKUST-01 Exopolysaccharide (SeNPs-EPS) Conjugate for Biomedical Applications

Exopolysaccharides (EPS) are exogenous microbial metabolites generated predominantly during the development of bacteria. They have several biological potentials, including antibacterial, antioxidant, and anticancer actions. Polysaccharide-coated nanoparticles have high biological activity and are used in treatments and diagnostics. In this research, selenium nanoparticles (SeNPs) are synthesized and conjugated with bacterial (Bacillus sp. MKUST-01) exopolysaccharide (EPS). Initially, the creation of SeNPs conjugates was verified through UV-Vis spectral examination, which exhibited a prominent peak at 264 nm. Additionally, X-ray diffraction (XRD) analysis further substantiated the existence of crystalline Se, as evidenced by a robust reflection at 29.78°. Another reflection observed at 23.76° indicated the presence of carbon originating from the EPS. Fourier transform infrared spectroscopy (FT-IR) analysis of the EPS capped with SeNPs displayed characteristic peaks at 3425 cm-1, 2926 cm-1, 1639 cm-1, and 1411 cm-1, corresponding to the presence of O-H, C-H, C=O, and COO-groups. The SeNPs themselves were found to possess elongated rod-shaped structures with lengths ranging from 250 to 550 nm and a diameter of less than 70 nm, as confirmed using scanning electron microscopy and particle size analysis. In contrast to the SeNPs, the SeNPs-EPS conjugates showed no hemolytic activity. The overall antioxidant activity of SeNPs-EPS conjugates outperformed 20% higher than SeNPs and EPS. Additionally, experimental observations involving gnotobiotic Artemia nauplii experiments were also recorded, such as the supplementation of EPS and SeNPs-EPS conjugates corresponding to enhanced growth and increased survival rates compared to Artemia nauplii fed with SeNPs and a microalgal diet.

Development and Characterization of Bio-Based Composite Films for Food Packing Applications Using Boiled Rice Water and Pistacia vera Shells

Customer demand for natural packaging materials in the food industry has increased. Biocomposite films developed using boiled rice water could be an eco-friendly and cost-effective packaging product in the future. This study reports the development of bio-based films using waste materials, such as boiled rice water (matrix) and Pistacia vera shells (reinforcement material), using an adapted solution casting method. Several film combinations were developed using various concentrations of plasticizing agent (sorbitol), thickening agent (oil and agar), and stabilizing agents (Arabic gum, corn starch, and Pistacia vera shell powder). Various packaging properties of the film were analyzed and examined to select the best bio-based film for food packaging applications. The film fabricated with Pistacia vera shell powder in the biocomposite film exhibited a reduced water solubility, swelling index, and moisture content, as compared to polyethene packaging material, whereas the biocomposite film exhibited poor antimicrobial properties, high vapor transmission rate, and high biodegradability rate. The packaging properties and characterization of the film indicated that the boiled rice water film with Pistacia vera shell powder was suitable for packaging material applications.

Evaluation of Photocatalytic, Antioxidant, and Antibacterial Efficacy of Almond Oil Capped Zinc Oxide Nanoparticles

In this study, ZnO nanoparticles (NPs) were synthesized in the presence of almond oil at various molar ratios of zinc acetate and sodium hydroxide, including 0.5:1, 0.75:1, 1:1, 1.25:1, and 1.5:1, to obtain pH values of 11, 10, 9, 8, and 7, respectively. The XRD results revealed that ZnO NPs exhibit a hexagonal structure, with high crystallinity. SEM results showed that dense and large sized ZnO NPs were formed at pH 11, and relatively small (~30-40 nm) NPs were obtained at pH 9. The size distribution can be explained in terms of the presence of OH- ions at different pH levels. However, the larger size of the NPs at pH 7 compared to those at pH 8-11 were due to the coalescence of NPs suitable for antioxidant/antibacterial activities. ZnO NPs demonstrated a high degradation efficiency (~93%) in 90 min, with a high rate constant for Methyl Orange (MO), which is better than the previously reported rate. The larger sized almond oil capped ZnO NPs also showed excellent radical scavenging activity (94%) and are proven to be good carriers to resist Escherichia coli (E. coli) bacteria.

OralNet: Fused Optimal Deep Features Framework for Oral Squamous Cell Carcinoma Detection

Humankind is witnessing a gradual increase in cancer incidence, emphasizing the importance of early diagnosis and treatment, and follow-up clinical protocols. Oral or mouth cancer, categorized under head and neck cancers, requires effective screening for timely detection. This study proposes a framework, OralNet, for oral cancer detection using histopathology images. The research encompasses four stages: (i) Image collection and preprocessing, gathering and preparing histopathology images for analysis; (ii) feature extraction using deep and handcrafted scheme, extracting relevant features from images using deep learning techniques and traditional methods; (iii) feature reduction artificial hummingbird algorithm (AHA) and concatenation: Reducing feature dimensionality using AHA and concatenating them serially and (iv) binary classification and performance validation with three-fold cross-validation: Classifying images as healthy or oral squamous cell carcinoma and evaluating the framework's performance using three-fold cross-validation. The current study examined whole slide biopsy images at 100× and 400× magnifications. To establish OralNet's validity, 3000 cropped and resized images were reviewed, comprising 1500 healthy and 1500 oral squamous cell carcinoma images. Experimental results using OralNet achieved an oral cancer detection accuracy exceeding 99.5%. These findings confirm the clinical significance of the proposed technique in detecting oral cancer presence in histology slides.

Light-Driven Catalytic Activity of Green-Synthesized SnO2/WO3-x Hetero-nanostructures

This work reports an environmentally friendly and economically feasible green synthesis of monometallic oxides (SnO₂ and WO₃) and their corresponding mixed metal oxide (SnO₂/WO_3-x) nanostructures from the aqueous Psidium guajava leaf extract for light-driven catalytic degradation of a major industrial contaminant, methylene blue (MB). P. guajava is a rich source of polyphenols that acts as a bio-reductant as well as a capping agent in the synthesis of nanostructures. The chemical composition and redox behavior of the green extract were investigated by liquid chromatography-mass spectrometry and cyclic voltammetry, respectively. Results acquired by X-ray diffraction and Fourier transform infrared spectroscopy confirm the successful formation of crystalline monometallic oxides (SnO₂ and WO₃) and bimetallic SnO₂/WO_3-x hetero-nanostructures capped with polyphenols. The structural and morphological aspects of the synthesized nanostructures were analyzed by transmission electron microscopy and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy. Photocatalytic activity of the synthesized monometallic and hetero-nanostructures was investigated for the degradation of MB dye under UV light irradiation. Results indicate a higher photocatalytic degradation efficiency for mixed metal oxide nanostructures (93.5%) as compared to pristine monometallic oxides SnO₂ (35.7%) and WO₃ (74.5%). The hetero-metal oxide nanostructures prove to be better photocatalysts with reusability up to 3 cycles without any loss in degradation efficiency or stability. The enhanced photocatalytic efficiency is attributed to a synergistic effect in the hetero-nanostructures, efficient charge transportation, extended light absorption, and increased adsorption of dye due to the enlarged specific surface area.

Effectiveness of Nonfunctionalized Graphene Oxide Nanolayers as Nanomedicine against Colon, Cervical, and Breast Cancer Cells

Recent studies in nanomedicine have intensively explored the prospective applications of surface-tailored graphene oxide (GO) as anticancer entity. However, the efficacy of nonfunctionalized graphene oxide nanolayers (GRO-NLs) as an anticancer agent is less explored. In this study, we report the synthesis of GRO-NLs and their in vitro anticancer potential in breast (MCF-7), colon (HT-29), and cervical (HeLa) cancer cells. GRO-NLs-treated HT-29, HeLa, and MCF-7 cells showed cytotoxicity in the MTT and NRU assays via defects in mitochondrial functions and lysosomal activity. HT-29, HeLa, and MCF-7 cells treated with GRO-NLs exhibited substantial elevations in ROS, disturbances of the mitochondrial membrane potential, an influx of Ca²⁺, and apoptosis. The qPCR quantification showed the upregulation of caspase 3, caspase 9, bax, and SOD1 genes in GRO-NLs-treated cells. Western blotting showed the depletion of P21, P53, and CDC25C proteins in the above cancer cell lines after GRO-NLs treatment, indicating its function as a mutagen to induce mutation in the P53 gene, thereby affecting P53 protein and downstream effectors P21 and CDC25C. In addition, there may be a mechanism other than P53 mutation that controls P53 dysfunction. We conclude that nonfunctionalized GRO-NLs exhibit prospective biomedical application as a putative anticancer entity against colon, cervical, and breast cancers.

Antimicrobial, anticancer, and biofilm inhibition studies of highly reduced graphene oxide (HRG): In vitro and in silico analysis

Background: Bacterial infections and cancers may cause various acute or chronic diseases, which have become serious global health issues. This requires suitable alternatives involving novel and efficient materials to replace ineffective existing therapies. In this regard, graphene composites are being continuously explored for a variety of purposes, including biomedical applications, due to their remarkable properties.

Methods: Herein, we explore, in-vitro, the different biological properties of highly reduced graphene oxide (HRG), including anti-cancer, anti-bacterial, and anti-biofilm properties. Furthermore, to analyze the interactions of graphene with proteins of microbes, in silico docking analysis was also carried out. To do this, HRG was prepared using graphene oxide as a precursor, which was further chemically reduced to obtain the final product. The as-prepared HRG was characterized using different types of microscopic and spectroscopic techniques.

Results: The HRG revealed significant cytotoxic ability, using a dose-dependent anti-cell proliferation approach, which substantially killed human breast cancer cells (MCF-7) with IC50 of 29.51 ± 2.68 μg/mL. The HRG demonstrated efficient biological properties, i.e., even at low concentrations, HRG exhibited efficient anti-microbial properties against a variety of microorganisms. Among the different strains, Gram-positive bacteria, such as B. subtilis, MRSA, and S. aureus are more sensitive to HRG compared to Gram-negative bacteria. The bactericidal properties of HRG are almost similar to a commercially available effective antibiotic (ampicillin). To evaluate the efficacy of HRG against bacterial biofilms, Pseudomonas aeruginosa and MRSA were applied, and the results were compared with gentamycin and ampicillin, which are commonly applied standard antibiotics. Notably, HRG demonstrated high inhibition (94.23%) against P.aeruginosa, with lower MIC (50 μg/mL) and IC50 (26.53 μg/mL) values, whereas ampicillin and gentamicin showed similar inhibition (90.45% and 91.31% respectively) but much higher MIC and IC50 values.

Conclusion: Therefore, these results reveal the excellent biopotential of HRG in different biomedical applications, including cancer therapy; antimicrobial activity, especially anti-biofilm activity; and other biomedicine-based therapies. Based on the molecular docking results of Binding energy, it is predicted that pelB protein and HRG would form the best stable docking complex, and high hydrogen and hydrophobic interactions between the pelB protein and HRG have been revealed. Therefore, we conclude that HRG could be used as an antibiofilm agent against P. aeruginosa infections.

Cerium Oxide/Graphene Oxide Hybrid: Synthesis, Characterization, and Evaluation of Anticancer Activity in a Breast Cancer Cell Line (MCF-7)

In the present study, we used a simple ultrasonic approach to develop a Cerium oxide/Graphene oxide hybrid (CeO₂/GO hybrid) nanocomposite system. Particle size analysis, Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and X-ray Diffraction (XRD) have been used to analyze the physio-chemical characteristics of the developed nanocomposite. The synthesized hybrid system has also been examined to assess its anticancer capability against MCF-7 cell lines and normal cell lines at different sample concentrations, pH values, and incubation intervals using an antiproliferative assay test. The test results demonstrate that as sample concentration rises, the apoptotic behavior of the CeO₂/GO hybrid in the MCF-7 cell line also rises. The IC₅₀ was 62.5 µg/mL after 72 h of incubation. Cytotoxicity of cisplatin bound CeO₂/GO hybrid was also tested in MCF-7 cell lines. To identify apoptosis-associated alterations of cell membranes during the process of apoptosis, a dual acridine orange/ethidium bromide (AO/EB) fluorescence staining was carried out at three specified doses (i.e., 1000 µg/mL, 250 µg/mL, and 62.5 µg/mL of CeO₂/GO hybrid). The color variations from both live (green) and dead (red) cells were examined using fluorescence microscopy under in vitro conditions. The quantitative analysis was performed using flow cytometry to identify the cell cycle at which the maximum number of MCF-7 cells had been destroyed as a result of interaction with the developed CeO₂/GO hybrid (FACS study). According to the results of the FACS investigation, the majority of cancer cells were inhibited at the R3 (G2/M) phase. Therefore, the CeO₂/GO hybrid has successfully showed enhanced anticancer efficacy against the MCF-7 cell line at the IC50 concentration. According to the current study, the CeO₂/GO platform can be used as a therapeutic platform for breast cancer. The synergetic effects of the developed CeO₂/GO hybrid with the MCF-7 cell line are presented.

Diversity of Citrullus colocynthis (L.) Schrad Seeds Extracts: Detailed Chemical Profiling and Evaluation of Their Medicinal Properties

Seeds and fruits of Citrullus colocynthis have been reported to possess huge potential for the development of phytopharmaceuticals with a wide range of biological activities. Thus, in the current study, we are reporting the potential antimicrobial and anticancer properties of C. colocynthis seeds extracted with solvents of different polarities, including methanol (M.E.), hexane (H.E.), and chloroform (C.E.). Antimicrobial properties of C. colocynthis seeds extracts were evaluated on Gram-positive and Gram-negative bacteria, whereas, anticancer properties were tested on four different cell lines, including HepG2, DU145, Hela, and A549. All the extracts have demonstrated noteworthy antimicrobial activities with a minimum inhibitory concentration (MIC) ranging from 0.9-62.5 µg/mL against Klebsiella planticola and Staphylococcus aureus; meanwhile, they were found to be moderately active (MIC 62.5-250 µg/mL) against Escherichia coli and Micrococcus luteus strains. Hexane extracts have demonstrated the highest antimicrobial activity against K. planticola with an MIC value of 0.9 µg/mL, equivalent to that of the standard drug ciprofloxacin used as positive control in this study. For anticancer activity, all the extracts of C. colocynthis seeds were found to be active against all the tested cell lines (IC₅₀ 48.49-197.96 µg/mL) except for the chloroform extracts, which were found to be inactive against the HepG2 cell line. The hexane extract was found to possess the most prominent anticancer activity when compared to other extracts and has demonstrated the highest anticancer activity against the DU145 cell line with an IC₅₀ value of 48.49 µg/mL. Furthermore, a detailed phytoconstituents analysis of all the extracts of C. colocynthis seeds were performed using GC-MS and GC-FID techniques. Altogether, 43 phytoconstituents were identified from the extracts of C. colocynthis seeds, among which 21, 12, and 16 components were identified from the H.E., C.E., and M.E. extracts, respectively. Monoterpenes (40.4%) and oxygenated monoterpenes (41.1%) were the most dominating chemical class of compounds from the hexane and chloroform extracts, respectively; whereas, in the methanolic extract, oxygenated aliphatic hydrocarbons (77.2%) were found to be the most dominating chemical class of compounds. To the best of our knowledge, all the phytoconstituents identified in this study are being reported for the first time from the C. colocynthis.

Hybrid Nanoparticles of Manganese Oxide and Highly Reduced Graphene Oxide for Photodynamic Therapy

BACKGROUND

Graphene-based nanomaterials possess unique optical, physicochemical and biomedical properties which make them potential tools for imaging and therapy. Manganese oxide nanoparticles are attractive candidates for contrast agents in magnetic resonance imagint (MRI). We used manganese oxide (Mn3O4) and highly reduced graphene oxide (HRG) to synthesize hybrid nanoparticles (HRG-Mn3O4) and tested their efficacy for photodynamic therapy (PDT) in breast cancer cells.

METHODS

The newly synthesized nanoparticles were characterized by transmission electron microscopy (TEM), energy-dispersive X-ray (EDX) spectroscopy, UV-visible spectroscopy, Fourier-transform infrared (FT-IR) spectroscopy, thermogravimetry, and X-ray diffraction (XRD) analyses. We used standard protocols of cytotoxicity and PDT after exposing A549 cells to various concentrations of hybrid nanoparticles (HRG-Mn3O4). We also performed fluorescence microscopy for live/dead cellular analysis. A549 cells were incubated with nanoparticles for 24 h and stained with fluorescein diacetate (green emission for live cells) and propidium iodide (red emission for dead cells) to visualize live and dead cells, respectively.

RESULTS

The cell viability analysis showed that more than 98% of A549 cells survived even after the exposure of a high concentration (100 μg/mL) of nanomaterials. These results confirmed that the HRG-Mn3O4 nanoparticles are nontoxic and biocompatible at physiological conditions. When the cell viability analysis was performed after laser irradiation, we observed significant and concentration-dependent cytotoxicity of HRG-Mn3O4 as compared to Mn3O4 nanoparticles. Fluorescence microscopy showed that almost 100% cells were viable when treated with phosphate buffered saline or Mn3O4 while only few dead cells were detected after exposure of HRG-Mn3O4 nanoparticles. However, laser irradiation resulted in massive cellular damage by HRG-Mn3O4 nanoparticles which was directly related to the generation of reactive oxygen species (ROS).

CONCLUSIONS

HRG-Mn3O4 hybrid nanoparticles are stable, biocompatible, nontoxic, and possess therapeutic potential for photodynamic therapy of cancer. Further studies are warranted to explore the MRI imaging ability of these nanomaterials using animal models of cancer.

Green Synthesized Silver Nanoparticle-Loaded Liposome-Based Nanoarchitectonics for Cancer Management: In Vitro Drug Release Analysis

Silver nanoparticles act as antitumor agents because of their antiproliferative and apoptosis-inducing properties. The present study aims to develop silver nanoparticle-loaded liposomes for the effective management of cancer. Silver nanoparticle-encapsulated liposomes were prepared using the thin-film hydration method coupled with sonication. The prepared liposomes were characterized by DLS (Dynamic Light Scattering analysis), FESEM (Field Emission Scanning Electron Microscope), and FTIR (Fourier Transform Infrared spectroscopy). The in vitro drug release profile of the silver nanoparticle-loaded liposomes was carried out using the dialysis bag method and the drug release profile was validated using various mathematical models. A high encapsulation efficiency of silver nanoparticle-loaded liposome was observed (82.25%). A particle size and polydispersity index of 172.1 nm and 0.381, respectively, and the zeta potential of -21.5 mV were recorded. FESEM analysis revealed spherical-shaped nanoparticles in the size range of 80-97 nm. The in vitro drug release profile of the silver nanoparticle-loaded liposomes was carried out using the dialysis bag method in three different pHs: pH 5.5, pH 6.8, and pH 7.4. A high silver nanoparticle release was observed in pH 5.5 which corresponds to the mature endosomes of tumor cells; 73.32 ± 0.68% nanoparticle was released at 72 h in pH 5.5. Among the various mathematical models analyzed, the Higuchi model was the best-fitted model as there is the highest value of the correlation coefficient which confirms that the drug release follows the diffusion-controlled process. From the Korsmeyer-Peppas model, it was confirmed that the drug release is based on anomalous non-Fickian diffusion. The results indicate that the silver nanoparticle-loaded liposomes can be used as an efficient drug delivery carrier to target cancer cells of various types.

Green Synthesis of Silver Nanoparticles Using Aerial Part Extract of the Anthemis pseudocotula Boiss. Plant and Their Biological Activity

Green syntheses of metallic nanoparticles using plant extracts as effective sources of reductants and stabilizers have attracted decent popularity due to their non-toxicity, environmental friendliness and rapid nature. The current study demonstrates the ecofriendly, facile and inexpensive synthesis of silver nanoparticles (AP-AgNPs) using the extract of aerial parts of the Anthemis pseudocotula Boiss. plant (AP). Herein, the aerial parts extract of AP performed a twin role of a reducing as well as a stabilizing agent. The green synthesized AP-AgNPs were characterized by several techniques such as XRD, UV-Vis, FT-IR, TEM, SEM and EDX. Furthermore, the antimicrobial and antibiofilm activity of as-prepared AP-AgNPs were examined by a standard two-fold microbroth dilution method and tissue culture plate methods, respectively, against several Gram-negative and Gram-positive bacterial strains and fungal species such as Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), multidrug-resistant Pseudomonas aeruginosa (MDR-PA) and Acinetobacter baumannii (MDR-AB), methicillin-resistant S. aureus (MRSA) and Candida albicans (C. albicans) strains. The antimicrobial activity results clearly indicated that the Gram-negative bacteria MDR-PA was most affected by AgNPs as compared to other Gram-negative and Gram-positive bacteria and fungi C. albicans. Whereas, in the case of antibiofilm activity, it has been found that AgNPs at 0.039 mg/mL, inhibit biofilms formation of Gram-negative bacteria i.e., MDR-PA, E. coli, and MDR-AB by 78.98 ± 1.12, 65.77 ± 1.05 and 66.94 ± 1.35%, respectively. On the other hand, at the same dose (i.e., 0.039 mg/mL), AP-AgNPs inhibits biofilm formation of Gram-positive bacteria i.e., MRSA, S. aureus and fungi C. albicans by 67.81 ± 0.99, 54.61 ± 1.11 and 56.22 ± 1.06%, respectively. The present work indicates the efficiency of green synthesized AP-AgNPs as good antimicrobial and antibiofilm agents against selected bacterial and fungal species.

Development of Metallo (Calcium/Magnesium) Polyurethane Nanocomposites for Anti-Corrosive Applications

Long-term corrosion protection of metals might be provided by nanocomposite coatings having synergistic qualities. In this perspective, rapeseed oil-based polyurethane (ROPU) and nanocomposites with calcium and magnesium ions were designed. The structure of these nanocomposites was established through Fourier-transform infrared spectroscopy (FT-IR). The morphological studies were carried out using scanning electron microscopy (SEM) as well as transmission electron microscopy (TEM). Their thermal characteristics were studied using thermogravimetric analysis (TGA). Electrochemical experiments were applied for the assessment of the corrosion inhibition performance of these coatings in 3.5 wt. % NaCl solution for 7 days. After completion of the test, the results revealed a very low i_corr value of 7.73 × 10^-10 A cm^-2, a low corrosion rate of 8.342 × 10^-5 mpy, impedance 1.0 × 10⁷ Ω cm², and phase angle (approx 90°). These findings demonstrated that nanocomposite coatings outperformed ordinary ROPU and other published methods in terms of anticorrosive activity. The excellent anti-corrosive characteristic of the suggested nanocomposite coatings opens up new possibilities for the creation of advanced high-performance coatings for a variety of metal industries.

Development and Validation for Quantification of Cephapirin and Ceftiofur by Ultraperformance Liquid Chromatography with Triple Quadrupole Mass Spectrometry

Cross contamination of β-lactams is one of the highest risks for patients using pharmaceutical products. Penicillin and some non-penicillin β-lactams may cause potentially life-threatening allergic reactions. The trace detection of β-lactam antibiotics in cleaning rinse solutions of common reactors and manufacturing aids in pharmaceutical facilities is very crucial. Therefore, the common facilities adopt sophisticated cleaning procedures and develop analytical methods to assess traces of these compounds in rinsed solutions. For this, a highly sensitive and reproducible ultra-performance liquid chromatography with triple quadrupole mass spectrometry (UHPLC-MS/MS) method was developed for the analysis of Cephapirin and Ceftiofur. As per the FDA guidelines described in FDA-2011-D-0104, the contamination of these β-lactam antibiotics must be regulated. The analysis was performed on an XBridge C18 column with 100 mm length, 4.6 mm diameter, and 3.5 µm particle size at an oven temperature of about 40 °C. The mobile phase was composed of 0.15% formic acid in water and acetonitrile as mobile phases A and B, and a flow rate was set to 0.6 mL/min. The method was validated for Cephapirin and Ceftiofur. The quantification precision and accuracy were determined to be the lowest limit of detection 0.15 parts per billion (ppb) and the lowest limit of quantification 0.4 ppb. This method was linear in the range of 0.4 to 1.5 ppb with the determination of coefficient (R2 > 0.99). This sensitive and fast method was fit-for-purpose for detecting and quantifying trace amounts of β-lactam contamination, monitoring cross contamination in facility surface cleaning, and determining the acceptable level of limits for regulatory purposes.

Surface-coated magnetic nanostructured materials for robust bio-catalysis and biomedical applications-A review

BACKGROUND

Enzymes based bio-catalysis has wide range of applications in various chemical and biological processes. Thus, the process of enzymes immobilization on suitable support to obtain highly active and stable bio-catalysts has great potential in industrial applications. Particularly, surface-modified magnetic nanomaterials have garnered a special interest as versatile platforms for biomolecules/enzyme immobilization.

AIM OF REVIEW

This review spotlights recent progress in the immobilization of various enzymes onto surface-coated multifunctional magnetic nanostructured materials and their derived nano-constructs for multiple applications. Conclusive remarks, technical challenges, and insightful opinions on this field of research which are helpful to expand the application prospects of these materials are also given with suitable examples.

KEY SCIENTIFIC CONCEPTS OF REVIEW

Nanostructured materials, including surface-coated magnetic nanoparticles have recently gained immense significance as suitable support materials for enzyme immobilization, due to their large surface area, unique functionalities, and high chemical and mechanical stability. Besides, magnetic nanoparticles are less expensive and offers great potential in industrial applications due to their easy recovery and separation form their enzyme conjugates with an external magnetic field. Magnetic nanoparticles based biocatalytic systems offer a wide-working temperature, pH range, increased storage and thermal stabilities. So far, several studies have documented the application of a variety of surface modification and functionalization techniques to circumvent the aggregation and oxidation of magnetic nanoparticles. Surface engineering of magnetic nanoparticles (MNPs) helps to improve the dispersion stability, enhance mechanical and physicochemical properties, upgrade the surface activity and also increases enzyme immobilization capabilities and biocompatibility of the materials. However, several challenges still need to be addressed, such as controlled synthesis of MNPs and clinical aspects of these materials require consistent research from multidisciplinary scientists to realize its practical applications.

Pyrene Functionalized Highly Reduced Graphene Oxide-palladium Nanocomposite: A Novel Catalyst for the Mizoroki-Heck Reaction in Water

The formation of a C-C bond through Mizoroki-Heck cross-coupling reactions in water with efficient heterogeneous catalysts is a challenging task. In this current study, a highly reduced graphene oxide (HRG) immobilized palladium (Pd) nanoparticle based catalyst (HRG-Py-Pd) is used to catalyze Mizoroki-Heck cross-coupling reactions in water. During the preparation of the catalyst, amino pyrene is used as a smart functionalizing ligand, which offered chemically specific binding sites for the effective and homogeneous nucleation of Pd NPs on the surface of HRG, which significantly enhanced the physical stability and dispersibility of the resulting catalyst in an aqueous medium. Microscopic analysis of the catalyst revealed a uniform distribution of ultrafine Pd NPs on a solid support. The catalytic properties of HRG-Py-Pd are tested towards the Mizoroki-Heck cross-coupling reactions of various aryl halides with acrylic acid in an aqueous medium. Furthermore, the catalytic efficacy of HRG-Py-Pd is also compared with its non-functionalized counterparts such as HRG-Pd and pristine Pd NPs (Pd-NPs). Using the HRG-Py-Pd nanocatalyst, the highest conversion of 99% is achieved in the coupling reaction of 4-bromoanisol and acrylic acid in an aqueous solution in a relatively short period of time (3 h), with less quantity of catalyst (3 mg). Comparatively, pristine Pd NPs delivered lower conversion (∼92%) for the same reaction required a long reaction time and a large amount of catalyst (5.3 mg). Indeed, the conversion of the reaction further decreased to just 40% when 3 mg of Pd-NPs was used which was sufficient to produce 99% conversion in the case of HRG-Py-Pd. On the other hand, HRG-Pd did not deliver any conversion and was ineffective even after using a high amount of catalyst and a longer reaction time. The inability of the HRG-Pd to promote coupling reactions can be attributed to the agglomeration of Pd NPs which reduced the dispersion quality of the catalyst in water. Therefore, the high aqueous stability of HRG-Py-Pd due to smart functionalization can be utilized to perform other organic transformations in water which was otherwise not possible.

Pulicaria undulata Extract-Mediated Eco-Friendly Preparation of TiO2 Nanoparticles for Photocatalytic Degradation of Methylene Blue and Methyl Orange

Eco-friendly approaches for the preparation of nanomaterials have recently attracted considerable attention of scientific community due to rising environmental distresses. The aim of the current study is to prepare titanium dioxide (TiO₂) nanoparticles (NPs) using an eco-friendly approach and investigate their performance for the photocatalytic degradation of hazardous organic dyes. For this, TiO₂ NPs were prepared by using the aqueous extract of the Pulicaria undulata (L.) plant in a single step at room temperature. Energy-dispersive X-ray spectroscopy established the presence of both titanium and oxygen in the sample. X-ray diffraction revealed the formation of crystalline, anatase-phase TiO₂ NPs. On the other hand, transmission election microscopy confirmed the formation of spherical shaped NPs. The presence of residual phytomolecules as capping/stabilization agents is confirmed by UV-vis analysis and Fourier-transform Infrared spectroscopy. Indeed, in the presence of P. undulata, the anatase phase of TiO₂ is stabilized at a significantly lower temperature (100 °C) without using any external stabilizing agent. The green synthesized TiO₂ NPs were used to investigate their potential for the photocatalytic degradation of hazardous organic dyes including methylene blue and methyl orange under UV-visible light irradiation. Due to the small size and high dispersion of NPs, almost complete degradation (∼95%) was achieved in a short period of time (between 1 and 2 h). No significant difference in the photocatalytic activity of the TiO₂ NPs was observed even after repeated use (three times) of the photocatalyst. Overall, the green synthesized TiO₂ NPs exhibited considerable potential for fast and eco-friendly removal of harmful organic dyes.

Advances in Graphene/Inorganic Nanoparticle Composites for Catalytic Applications

Graphene-based nanocomposites with inorganic (metal and metal oxide) nanoparticles leads to materials with high catalytic activity for a variety of chemical transformations. Graphene and its derivatives such as graphene oxide, highly reduced graphene oxide, or nitrogen-doped graphene are excellent support materials due to their high surface area, their extended π-system, and variable functionalities for effective chemical interactions to fabricate nanocomposites. The ability to fine-tune the surface composition for desired functionalities enhances the versatility of graphene-based nanocomposites in catalysis. This review summarizes the preparation of graphene/inorganic NPs based nanocomposites and their use in catalytic applications. We discuss the large-scale synthesis of graphene-based nanomaterials. We have also highlighted the interfacial electronic communication between graphene/inorganic nanoparticles and other factors resulting in increased catalytic efficiencies.

In-silico study of seaweed secondary metabolites as AXL kinase inhibitors

AXL kinase is an attractive cancer target for drug design and it is involved in different cancers. A set of molecule databases with 1072 secondary metabolites from seaweeds were screened against the AXL kinase active site and eight molecules were shortlisted for further studies. From the docking analysis of the complexes, four molecules GA011, BE005, BC010, and BC005 are showing prominent binging. From the 100 ns of molecular dynamics simulations and ligand-bound complex MM-PBSA free energy analysis, two molecules BC010 (ΔG = −135.38 kJ/mol) and BE005 (ΔG = −141.72 kJ/mol) are showing molecule stability in the active site also showing very strong binding free energies. It suggests these molecules could be the potent molecules for AXL kinase.

Engineered Nanomaterials in Soil: Their Impact on Soil Microbiome and Plant Health

A staggering number of nanomaterials-based products are being engineered and produced commercially. Many of these engineered nanomaterials (ENMs) are finally disposed into the soil through various routes in enormous quantities. Nanomaterials are also being specially tailored for their use in agriculture as nano-fertilizers, nano-pesticides, and nano-based biosensors, which is leading to their accumulation in the soil. The presence of ENMs considerably affects the soil microbiome, including the abundance and diversity of microbes. In addition, they also influence crucial microbial processes, such as nitrogen fixation, mineralization, and plant growth promoting activities. ENMs conduct in soil is typically dependent on various properties of ENMs and soil. Among nanoparticles, silver and zinc oxide have been extensively prepared and studied owing to their excellent industrial properties and well-known antimicrobial activities. Therefore, at this stage, it is imperative to understand how these ENMs influence the soil microbiome and related processes. These investigations will provide necessary information to regulate the applications of ENMs for sustainable agriculture and may help in increasing agrarian production. Therefore, this review discusses several such issues.

A-π-D-π-A-Based Small Molecules for OTFTs Containing Diketopyrrolopyrrole as Acceptor Units

A-π-D-π-A-based small molecules 6,6′-((thiophene-2,5-diylbis(ethyne-2,1-diyl))bis(thiophene-5,2-diyl))bis(2,5-bis(2-ethylhexyl)-3-(thiophen-2-yl)-2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dione) (TDPP-T) and 6,6′-(((2,3-dihydrothieno[3,4-b][1,4]dioxine-5,7-diyl)bis(ethyne-2,1-diyl))bis(thiophene-5,2-diyl))bis(2,5-bis(2-ethylhexyl)-3-(thiophen-2-yl)-2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dione) (TDPP-EDOT) have been designed and synthesized. The diketopyrrolopyrrole acts as an electron acceptor, while the thiophene or 3,4-ethylenedioxythiophene acts as an electron donor. The donor–acceptor groups are connected by an ethynyl bridge to further enhance the conjugation. The optoelectronics, electrochemical, and thermal properties have been investigated. Organic thin film transistor (OTFT) devices prepared from TDPP-T and TDPP-EDOT have shown p-type mobility. In as cast films, TDPP-T and TDPP-EDOT have shown a hole mobility of 5.44 × 10⁻⁶ cm² V⁻¹ s⁻¹ and 4.13 × 10⁻⁶ cm² V⁻¹ s⁻¹, respectively. The increase in the mobility of TDPP-T and TDPP-EDOT OTFT devices was observed after annealing at 150 °C, after which the mobilities were 3.11 × 10⁻⁴ cm² V⁻¹ s⁻¹ and 2.63 × 10⁻⁴ cm² V⁻¹ s⁻¹, respectively.

Impact of Macrodiols on the Morphological Behavior of H12MDI/HDO-Based Polyurethane Elastomer

In this study, we evaluated the morphological behavior of polyurethane elastomers (PUEs) by modifying the soft segment chain length. This was achieved by increasing the soft segment molecular weight (Mn = 400–4000 gmol⁻¹). In this regard, polycaprolactone diol (PCL) was selected as the soft segment, and 4,4′-cyclohexamethylene diisocyanate (H₁₂MDI) and 1,6-hexanediol (HDO) were chosen as the hard segments. The films were prepared by curing polymer on Teflon surfaces. Fourier transform infrared spectroscopy (FTIR) was utilized for functional group identification in the prepared elastomers. FTIR peaks indicated the disappearance of −NCO and −OH groups and the formation of urethane (NHCOO) groups. The morphological behavior of the synthesized polymer samples was also elucidated using scanning electron microscopy (SEM) and atomic force microscopy (AFM) techniques. The AFM and SEM results indicated that the extent of microphase separation was enhanced by an increase in the molecular weight of PCL. The phase separation and degree of crystallinity of the soft and hard segments were described using X-ray diffraction (XRD). It was observed that the degree of crystallinity of the synthesized polymers increased with an increase in the soft segment’s chain length. To evaluate hydrophilicity/hydrophobicity, the contact angle was measured. A gradual increase in the contact angle with distilled water and diiodomethane (38.6°–54.9°) test liquids was observed. Moreover, the decrease in surface energy (46.95–24.45 mN/m) was also found to be inconsistent by increasing the molecular weight of polyols.

Enhanced Apoptosis by Functionalized Highly Reduced Graphene Oxide and Gold Nanocomposites in MCF-7 Breast Cancer Cells

Graphene nanocomposites have gained significant interest in a variety of biological applications due to their unique properties. Herein, we have studied the apoptosis-inducing ability and anticancer properties of functionalized highly reduced graphene oxide (HRG) and gold nanoparticles (Au NPs)-based nanocomposites (AP-HRG-Au). Samples were prepared under facile conditions via simple stirring and ultrasonication. All the samples were tested for their anticancer properties against different human cancer cell lines including lung (A549), liver (HepG2), and breast (MCF-7) cancer cells using doxorubicin as a positive control. In order to enhance the solubility and bioavailability of the sample, HRG was functionalized with 1-aminopyrene (1-AP) as a stabilizing ligand. The ligand also facilitated the homogeneous growth of Au NPs on the surface of HRG by offering chemically specific binding sites. The synthesis of nanocomposites and the surface functionalization of HRG were confirmed by UV-Vis, powder X-ray diffraction, and Fourier transform infrared spectroscopy. The structure and morphology of the as-prepared nanocomposites were established by high-resolution transmission electron microscopy. Because of the functionalization, the AP-HRG-Au nanocomposite exhibited enhanced physical stability and high dispersibility. A comparative anticancer study of pristine HRG, nonfunctionalized HRG-Au, and 1-AP-functionalized AP-HRG-Au nanocomposites revealed the enhanced apoptosis ability of functionalized nanocomposites compared to the nonfunctionalized sample, whereas the pristine HRG did not show any anticancer ability against all tested cell lines. Both HRG-Au and AP-HRG-Au have induced a concentration-dependent reduction in cell viability in all tested cell lines after 48 h of exposure, with a significantly higher response in MCF-7 cells compared to the remaining cells. Therefore, MCF-7 cells were selected to perform detailed investigations using apoptosis assay, cell cycle analysis, and reactive oxygen species measurements. These results suggest that AP-HRG-Au induces enhanced apoptosis in human breast cancer cells.

Facile synthesis, physiochemical characterization and bio evaluation of sulfadimidine capped cobalt nanoparticles

Due to their less expensive, environment friendly nature, and their natural abundance of cobalt have attained more significant attention for the synthesis of cobalt nanoparticles. In the present study, we report the facile synthesis of cobalt nanoparticles using a straight forward chemical reduction approach of cobalt chloride with sodium borohydride and capping of sulfadimidine. sulfadimidine has strong capping eligibility on the surface of nanoparticles due to its chemical stability and is an applicable as stabilizer due to the existence of an amine bond. The as-synthesized sulfadimidine stabilized cobalt nanoparticles (Co-SD NPs) were characterized by using various spectroscopic and microscopic analysis like UV-Visible spectroscopy (UV-Vis), X-ray powder diffraction (XRD), scanning electron microscopy (SEM), High-Resolution Transmission electron microscopy (HR-TEM), and Fourier-transform infrared spectroscopy (FT-IR). The XRD analysis exhibited the triclinic crystal structure of the as-synthesized cobalt nanoparticles and FT-IR analysis confirmed the capping of sulfadimidine via monodentate interaction. The HR-TEM analysis displayed the size of the cobalt nanoparticles approximately 3-5 nm. The antibacterial properties of the sulfadimidine stabilized cobalt nanoparticles (Co-SD NPs) were tested against various bacterial strains such as Klebsiella pneumonia (KP), Escherichia coli (EC) and Pseudomonas syringae (PS) by using agar disc diffusion approach. The results of sulfadimidine capped cobalt nanoparticles displayed the enhanced biological properties against the tested gram-negative bacteria.

In vitro antimicrobial activity and comparison of the herbal extracts and sodium hypochlorite against primary plaque colonizers

NaClO is not suitable as a root canal irrigant because of its cytotoxicity. Good biocompatibility irrigants are required to have antibacterial activity. Many herbal products like Bee glue, Noni juice and Azadirachta indica have such properties. This study aims to investigate the possible effects of propolis, MCJ and Neem on bacterial infections and cytotoxicity in primary plaque colonizers. Direct contact and agar diffusion tests evaluated the antibacterial activity of herbal products against Fusobacterium, Candida albicans and Prevotella. The CCK 8 test determined the influence of these herbal products on the proliferation of human apical papilla stem cells (hSCAPs) and human periodontal fibroblasts (hPDLFs). A migration assay test was performed in addition to quantitative real-time PCR which measured osteogenic differentiation in hSCAPs. All herbal extracts tested in this study exhibited antibacterial activity comparable to NaClO against bacterial infections, while the strongest bacteriostatic effect was shown in the herbal treated group. These extracts had much weaker effects on the proliferation and migration of hSCAPs and hPDLFs as calculated by the CCK-8 assay against NaClO. Bee glue treatment had the most potent effect on osteogenic differentiation, followed by treatment with Noni juice and Azadirachta indica (Neem), while NaClO showed the lowest effect. For primary plaque colonizers of immature or advanced permanent teeth, Bee glue, Noni juice, and Azadirachta indica can be promising irrigants with good biocompatibility. Direct contact process and agar diffusion studies have tested the antibacterial activity against Fusobacterium, Candida albicans and Prevotella. The CCK 8 test determined the influence of these three plants on the proliferation of human apical papilla stem cells (hSCAPs) and human periodontal fibroblasts (hPDLFs). In order to examine migration ability, migration assay test was performed. Alizarin red staining, alkaline phosphatase (ALP) staining and quantitative real-time PCR measured osteo-/odontogenic differentiation in hSCAPs. All herbal extracts tested in this study exhibited antibacterial activity comparable to NaClO against bacterial infections, while the strongest bacteriostatic effect was shown in the treated group. These extracts had much weaker effects on the proliferation and migration of hSCAPs and hPDLFs as calculated by the CCK-8 assay against NaClO. Bee glue treatment had the most potent effect on osteo-odontogenic differentiation, followed by treatment with Noni juice and Azadirachta indica (Neem), while NaClO showed the lowest effect. For primary plaque colonizers of immature or advanced permanent teeth, Bee glue, Noni juice and Azadirachta indica (Neem) can be promising irrigants.

Dinuclear uranium(VI) salen coordination compound: an efficient visible-light-active catalyst for selective reduction of CO2 to methanol

A new dinuclear uranyl salen coordination compound, [(UO2)2(L)2]·2MeCN [L = 6,6'-((1E,1'E)-((2,2-dimethylpropane-1,3-diyl)bis(azaneylylidene))-bis(methaneylylidene))bis(2-methoxyphenol)], was synthesized using a multifunctional salen ligand to harvest visible light for the selective photocatalytic reduction of CO2 to MeOH. The assembling of the two U centers into one coordination moiety via a chelating-bridging doubly deprotonated tetradentate ligand allowed the formation of U centers with distorted pentagonal bipyramid geometry. Such construction of compounds leads to excellent activity for the photocatalytic reduction of CO2, permitting a production rate of 1.29 mmol g-1 h-1 of MeOH with an apparent quantum yield of 18%. Triethanolamine (TEOA) was used as a sacrificial electron donor to carry out the photocatalytic reduction of CO2. The selective methanol formation was purely a photocatalytic phenomenon and confirmed using isotopically labeled 13CO2 and product analysis by 13C-NMR spectroscopy. The spectroscopic studies also confirmed the interaction of CO2 with the molecule of the title complex. The results of these efforts made it possible to understand the reaction mechanism using ESI-mass spectrometry.

Facile synthesis of Pd@graphene nanocomposites with enhanced catalytic activity towards Suzuki coupling reaction

A facile and chemical specific method to synthesize highly reduced graphene oxide (HRG) and Pd (HRG@Pd) nanocomposite is presented. The HRG surfaces are tailored with amine groups using 1-aminopyrene (1-AP) as functionalizing molecules. The aromatic rings of 1-AP sit on the basal planes of HRG through π-π interactions, leaving amino groups outwards (similar like self-assembled monolayer on 2D substrates). The amino groups provide the chemically specific binding sites to the Pd nucleation which subsequently grow into nanoparticles. HRG@Pd nanocomposite demonstrated both uniform distribution of Pd nanoparticles on HRG surface as well as excellent physical stability and dispersibility. The surface functionalization was confirmed using, ultraviolet-visible (UV-Vis), Fourier transform infra-red and Raman spectroscopy. The size and distribution of Pd nanoparticles on the HRG and crystallinity were confirmed using high-resolution transmission electron microscopy and powder X-ray diffraction and X-ray photoelectron spectroscopy. The catalytic efficiency of highly reduced graphene oxide-pyrene-palladium nanocomposite (HRG-Py-Pd) is tested towards the Suzuki coupling reactions of various aryl halides. The kinetics of the catalytic reaction (Suzuki coupling) using HRG-Py-Pd nanocomposite was monitored using gas chromatography (GC).

Luminescent Complexes of Co(II), Ni(II), Cu(II), Zn(II)and Bi(III) with 2-Aminothiazole based Ligand and their Biological Studies

3-(thiazol-2-yl carbamoyl) propanoic acid was synthesized by the reaction of 2-aminothiazole and succinic anhydride, which was employed as ligand (LH) for further reaction with Co(II), Ni(II), Cu(II), Zn(II) and Bi(III) chlorides at ambient conditions to afford respective metal complexes, denoted as Co-L2, Ni-L2, Cu-L2, Zn-L2 and Bi-L3. Both the ligand LH and metal complexes were characterized by techniques FT-IR, 1H-NMR, 13C-NMR, powder XRD, TGA and conductometry. FT-IR and NMR studies revealed that ligand (LH) behaved in anisobidentate fashion via carboxylate moiety. The ligand and metal complexes are also screened for their antibacterial and antifungal potential and found non-significant activities by most of the complexes, luminescent studies were also made and found Bi-L3 appreciably luminescent.

Enhanced Antimicrobial Activity of Biofunctionalized Zirconia Nanoparticles

The effective interactions of nanomaterials with biological constituents play a significant role in enhancing their biomedicinal properties. These interactions can be efficiently enhanced by altering the surface properties of nanomaterials. In this study, we demonstrate the method of altering the surface properties of ZrO2 nanoparticles (NPs) to enhance their antimicrobial properties. To do this, the surfaces of the ZrO2 NPs prepared using a solvothermal method is functionalized with glutamic acid, which is an α-amino acid containing both COO- and NH4 + ions. The binding of glutamic acid (GA) on the surface of ZrO2 was confirmed by UV-visible and Fourier transform infrared spectroscopies, whereas the phase and morphology of resulting GA-functionalized ZrO2 (GA-ZrO2) was identified by X-ray diffraction and transmission electron microscopy. GA stabilization has altered the surface charges of the ZrO2, which enhanced the dispersion qualities of NPs in aqueous media. The as-prepared GA-ZrO2 NPs were evaluated for their antibacterial properties toward four strains of oral bacteria, namely, Rothia mucilaginosa, Rothia dentocariosa, Streptococcus mitis, and Streptococcus mutans. GA-ZrO2 exhibited increased antimicrobial activities compared with pristine ZrO2. This improved activity can be attributed to the alteration of surface charges of ZrO2 with GA. Consequently, the dispersion properties of GA-ZrO2 in the aqueous solution have increased considerably, which may have enhanced the interactions between the nanomaterial and bacteria.

Solvothermal Preparation and Electrochemical Characterization of Cubic ZrO₂ Nanoparticles/Highly Reduced Graphene (HRG) based Nanocomposites

A single-step solvothermal approach to prepare stabilized cubic zirconia (ZrO₂) nanoparticles (NPs) and highly reduced graphene oxide (HRG) and ZrO₂ nanocomposite (HRG@ZrO₂) using benzyl alcohol as a solvent and stabilizing ligand is presented. The as-prepared ZrO₂ NPs and the HRG@ZrO₂ nanocomposite were characterized using transmission electron microscopy (TEM) and X-ray diffraction (XRD), which confirmed the formation of ultra-small, cubic phase ZrO₂ NPs with particle sizes of ~2 nm in both reactions. Slight variation of reaction conditions, including temperature and amount of benzyl alcohol, significantly affected the size of resulting NPs. The presence of benzyl alcohol as a stabilizing agent on the surface of ZrO₂ NPs was confirmed using various techniques such as ultraviolet-visible (UV-vis), Fourier-transform infrared (FT-IR), Raman and XPS spectroscopies and thermogravimetric analysis (TGA). Furthermore, a comparative electrochemical study of both as-prepared ZrO₂ NPs and the HRG@ZrO₂ nanocomposites is reported. The HRG@ZrO₂ nanocomposite confirms electronic interactions between ZrO₂ and HRG when compared their electrochemical studies with pure ZrO₂ and HRG using cyclic voltammetry (CV).

Plant extracts as green reductants for the synthesis of silver nanoparticles: lessons from chemical synthesis

From conventional synthesis to green transformations: a brief literature overview and insight for the synthesis of Ag nanoparticles.