More reactive oxygen species generation facilitated by highly dispersed bimodal gold nanoparticle on the surface of Bi2WO6 for enhanced photocatalytic degradation of ofloxacin in water

CD44 mediated colon cancer targeting mutlifaceted lignin nanoparticles: Synthesis, in vitro characterization and in vivo efficacy studies

Hyaluronic acid (HA) coated irinotecan loaded lignin nanoparticles (HDLNPs) were synthesized using ionic interaction method. Optimized nanoparticles were characterized for their active chemotherapeutic targeting potential to CD44 receptors overly-expressed on cancer cells. Blood component interaction studies supported hemocompatible nature of HDLNPs and also demonstrated their sustained plasma residence property. Cell anti-proliferation and mitochondrial depolarization studies on HT-29 cells suggest significantly (p < 0.01) improved chemotherapeutic efficacy of HDLNPs. In vitro cell based studies showed that nanoparticles have retained antioxidant activity of lignin that can prevent cancer relapse. In vivo biodistribution studies in tumor-bearing Balb/c mice confirmed improved drug localization in tumor site for longer duration. Tumor regression and histopathological studies indicated the efficacy ofligand-assisted targeting chemotherapy over the conventional therapy. Hematological and biochemical estimation suggested that irinotecan-associated myelosuppression, liver steatosis and rare kidney failure can be avoided by its encapsulation in HA-coated lignin nanoparticles. HDLNPs were found to be stable over a period of 12 months.

Visible-light driven excellent photocatalytic degradation of ofloxacin antibiotic using BiFeO3 nanoparticles

The extensive exploration of multiferroic materials for degradation of contaminants and environmental remediation is promptly strengthened because of their distinct applications. BiFeO₃, a prominent class of multiferroics, have received immense attention in recent times. Present study reports the synthesis of a highly crystalline BiFeO₃ via facile combustion method. The prepared catalyst was characterized using different techniques like XRD, FTIR, FESEM, EDS, XPS, DRS and PL. From DRS results, the energy band gap of BiFeO₃ was computed as 2.1 eV which was suitable enough for its exploration as a visible light photocatalyst. Therefore, BiFeO₃ was efficiently utilized for the degradation of ofloxacin drug under the exposure of visible light. The obtained results depicted 80% ofloxacin degradation under optimized conditions (pH 8, 0.5 g/L catalyst dose and 10 mg/L drug concentration) in 180 min. Pseudo first order kinetics was followed with rate constant 0.0097 min^-1, as inferred from the kinetic studies. Furthermore, 64% TOC reduction was attained by utilizing the prepared catalyst under optimum conditions. Additionally, the photocatalytic experiments showed excellent degradation efficiency even after five cycles which demonstrated good stability of the fabricated catalyst.

Enhanced Sonocatalytic Performance of Non-Metal Graphitic Carbon Nitride (g-C3N4)/Coconut Shell Husk Derived-Carbon Composite

This study focused on the modification of graphitic carbon nitride (g-C3N4) using carbon which was obtained from the pyrolysis of coconut shell husk. The sonocatalytic performance of the synthesized samples was then studied through the degradation of malachite green. In this work, pure g-C3N4, pure carbon and carbon/g-C3N4 composites (C/g-C3N4) at different weight percentages were prepared and characterized by using XRD, SEM-EDX, FTIR, TGA and surface analysis. The effect of carbon amount in the C/g-C3N4 composites on the sonocatalytic performance was studied and 10 wt% C/g-C3N4 showed the best catalytic activity. The optimization study was conducted by using response surface methodology (RSM) with a central composite design (CCD) model. Three experimental parameters were selected in RSM including initial dye concentration (20 to 25 ppm), initial catalyst loading (0.3 to 0.5 g/L), and solution pH (4 to 8). The model obtained was found to be significant and reliable with R2 value (0.9862) close to unity. The degradation efficiency of malachite green was optimized at 97.11% under the conditions with initial dye concentration = 20 ppm, initial catalyst loading = 0.5 g/L, solution pH = 8 after 10 min. The reusability study revealed the high stability of 10 wt% C/g-C3N4 as sonocatalyst. In short, 10 wt% C/g-C3N4 has a high potential for industrial application since it is cost effective, reusable, sustainable, and provides good sonocatalytic performance.

Nitrogen doped carbon spheres from Tamarindus indica shell decorated with vanadium pentoxide; photoelectrochemical water splitting, photochemical hydrogen evolution & degradation of Bisphenol A

At present energy and environmental remediation are of highest priority for the well defined sustainability. Multifunctional materials that solve both the issues are on high demand. In the present work, a simple method has been followed to extract carbon spheres fromTamarindus indica(commonly known astamarind fruit) shelland doped with nitrogen (N-CS). Vanadium pentoxide nanoflakes were decorated aroundN-CS and the resultant is labeled as V₂O₅/N-CS nanocomposite. The spectroscopic, microscopic, elemental mapping and x-ray photoelectron spectroscopic characterization confirm the nitrogen doping and formation of hybrid material. N-CS, V₂O₅, and V₂O₅/N-CS nanocompositehave been evaluated for their efficiency to evolve hydrogen and for degradation of Bisphenol A (BPA) under visible light. In addition, electrocatalytic hydrogen evolution in presence of light has also been evaluated. The DRS spectrum proves the decrease in the bandgap of V₂O₅ upon its decoration around N-CS material. In a photochemical experiment, the V₂O₅/N-CS nanocomposite evolved 18,600 μmolg^-1 of H_2.Electrochemical hydrogen evolution has also been evaluated in presence of light and obtained the onset potential of -60mV with 52 mV dec^-1 Tafel slope value. Scavenger studies indicate superoxide radicals and hydroxyl radicals are the active species responsible for the degradation of BPA. BPA degradation pathway has been predicted with the support of LC-MS results of the intermediates. All these results indicate the synthesized nanocomposite could be an efficient, stable multifunctional material for photocatalytic applications.

Preparation of Mn2O3/MIL-100(Fe) composite and its mechanism for enhancing the photocatalytic removal of rhodamine B in water

In this study, Mn₂O₃/MIL-100(Fe) composite was successfully synthesized by the hydrothermal method and applied for photocatalytic removal of rhodamine B (RhB) in water. The physical and chemical properties of the synthesized materials were characterized by XRD, FTIR, SEM, UV-visible, and BET analyses. Experimental results showed a great enhancement in the photocatalytic ability of the Mn₂O₃/MIL-100(Fe) composite as compared to individual Mn₂O₃ or MIL-100(Fe) under visible light and persulfate activation. The affecting factors such as pH, photocatalyst dose, RhB concentration, and Na₂S₂O₈ concentration were investigated to find out the best conditions for efficient photocatalysis. By conducting a radical quenching test, all radicals of HO˙, SO₄˙^-, ¹O₂, and O₂˙^- were found to be important in photocatalytic decomposition. The mechanism was proposed for the enhancement of photocatalytic RhB removal via band potential calculation, charge separation, surface redox reaction, and key reactive oxidation species. With its durability, reusability, and high efficiency, the Mn₂O₃/MIL-100(Fe) composite emerges as a potential photocatalyst working under visible light for application in wastewater treatment.