Preparation and Spectrochemical characterization of Ni-doped ZnS nanocomposite for effective removal of emerging contaminants and hydrogen Production: Reaction Kinetics, mechanistic insights.

In this study, we report the successful synthesis of Ni-doped ZnS nanocomposite via a green route using ethanolic crude extract of Avena fatua. The as-synthesized nanocomposite was comprehensively characterized using Dynamic light scattering (DLS), Zeta potential, scanning electron microscopy (SEM), Transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), and Atomic force microscopy (AFM). These analyses provided detailed insights into the size, morphology, composition, surface properties, and structural characteristics of the nanocomposite. Subsequently, the synthesized nanocomposite was evaluated for their photocatalytic performance against the organic dye Methyl orange. Remarkably, the nanocomposite exhibited rapid and efficient degradation of Methyl orange, achieving 90 % degradation within only 30 min of irradiation under UV light. Moreover, the photocatalyst demonstrated an exceptional hydrogen production rate, reaching 167.73 µmolg-1h-1, which is approximately 4.5 times higher than that of its pristine counterparts. These findings highlight the significant potential of Ni-doped ZnS nanocomposite as highly efficient photocatalysts for wastewater treatment and hydrogen production applications.

Environmentally friendly protocol for the determination of sitagliptin phosphate in pharmaceutical preparations and biological fluids using l-tyrosine as a fluorescence probe.

A responsive spectrofluorometric method was developed for the determination of sitagliptin phosphate using l-tyrosine as a fluorescence probe. The fluorescence intensity of l-tyrosine was quenched with sitagliptin phosphate. The fluorescence intensity was recorded at 307 nm using a 272 nm excitation wavelength. The calibration plot between fluorescence intensity and the concentration of drug was linear in the range of 0.1 to 2.0 mM with a good correlation value of 0.997. The limit of detection and quantification were established to be 3.7 × 10-4 and 1.23 × 10-3  mM, respectively. Commonly used excipients did not interfere with sitagliptin phosphate measurement. The proposed method was used to measure the sitagliptin phosphate in its standard type, dosage form, and biological samples. The percent recovery ranged from 97.41-103.36%. The static quenching was shown to be responsible for quenching as indicated by the Stern-Volmer plot. The method was validated using ICH guidelines and profitably applied for the content uniformity test, resulting in a high percent recovery and small relative standard deviation. The proposed approach is effortless, susceptible, selective, economic, and provides a high precision and accuracy, and can be used to determine sitagliptin phosphate in the pharmaceutical industry.

Synthesis, Structural Elucidation and Pharmacological Applications of Cu(II) Heteroleptic Carboxylates.

Six heteroleptic Cu(II) carboxylates (1-6) were prepared by reacting 2-chlorophenyl acetic acid (L1), 3-chlorophenyl acetic acid (L2), and substituted pyridine (2-cyanopyridine and 2-chlorocyanopyridine). The solid-state behavior of the complexes was described via vibrational spectroscopy (FT-IR), which revealed that the carboxylate moieties adopted different coordination modes around the Cu(II) center. A paddlewheel dinuclear structure with distorted square pyramidal geometry was elucidated from the crystal data for complexes 2 and 5 with substituted pyridine moieties at the axial positions. The presence of irreversible metal-centered oxidation reduction peaks confirms the electroactive nature of the complexes. A relatively higher binding affinity was observed for the interaction of SS-DNA with complexes 2-6 compared to L1 and L2. The findings of the DNA interaction study indicate an intercalative mode of interaction. The maximum inhibition against acetylcholinesterase enzyme was caused for complex 2 (IC50 = 2 µg/mL) compared to the standard drug Glutamine (IC50 = 2.10 µg/mL) while the maximum inhibition was found for butyrylcholinesterase enzyme by complex 4 (IC50 = 3 µg/mL) compared to the standard drug Glutamine (IC50 = 3.40 µg/mL). The findings of the enzymatic activity suggest that the under study compounds have potential for curing of Alzheimer's disease. Similarly, complexes 2 and 4 possess the maximum inhibition as revealed from the free radical scavenging activity performed against DPPH and H2O2.

Eco-friendly approach for determination of moxifloxacin in pharmaceutical preparations and biological fluids through fluorescence quenching of eosin Y.

An easy, verified spectrofluorimetric approach was established for the investigation of moxifloxacin in pure forms, pharmaceutical preparations, and biological fluids. The approach involves forming a binary complex of moxifloxacin and eosin Y in an acetate buffer with a pH of 3.6. The highest quenching of eosin Y with moxifloxacin occurs at 545 nm. Several factors, such as pH, buffer type and concentration, and eosin Y concentration, were carefully studied. The calibration graph showed a linear relationship between fluorescence intensity and moxifloxacin concentrations between 0.2 and 10 µg mL-1 with a correlation coefficient of 0.998. It was determined that the detection and quantification limits were 0.0322 µg mL-1 and 0.0976 µg mL-1, respectively. The impact of common excipients was investigated, but no interferences were discovered. Standard forms of moxifloxacin, pharmaceuticals, and biological samples have all been studied using the established methodology. The method, which successfully complied with ICH requirements, was used for the analysis of moxifloxacin in its pure form, pharmaceutical dosage forms, and biological samples. The percentage recoveries obtained were ranged from 99.50 to 102.50% for pharmaceutical preparations and from 100.50 to 102.50% for human blood plasma and urine. Proposed mechanisms for the reaction between moxifloxacin and eosin Y.