Herein, we describe the development of a novel colorimetric sensor based on silver nanoparticles decoratively anchored onto a graphene oxide scaffold (AgNPs@GO) for the sensitive and selective determination of cefazolin in complex biological and environmental matrices. The nanocomposite was synthesized through an in-situ citrate-mediated reduction strategy, affording spherical silver nanoparticles with a mean diameter of 18.6 +/- 4.2 nm uniformly dispersed across the graphene oxide surface. Comprehensive characterization employing FE-SEM, FT-IR, and XRD confirmed the successful immobilization of highly crystalline, phase-pure silver nanoparticles onto the exfoliated carbon support. The sensor operates on the principle of analyte-induced aggregation, transduced as a ratiometric change in the localized surface plasmon resonance absorption (A(650)/A(400)). Under optimized conditions (pH 7.0, 50 mM NaCl, 12 min incubation, 0.25 mg & centerdot;mL(-1) AgNPs@GO), the probe exhibited a linear response toward cefazolin across the concentration range of 0.5 to 75.0 & micro;M, with a limit of detection of 0.16 & micro;M. The sensor demonstrated excellent selectivity against structurally analogous antibiotics and common coexisting species, with notable tolerance to ionic strength up to 100 mM NaCl. Practical applicability was validated through quantitative recovery of cefazolin from spiked human serum (96.0-98.9%), river water (98.0-99.6%), and wastewater effluent (94.0-97.8%), with results statistically equivalent to those obtained by high-performance liquid chromatography. This AgNPs@GO platform reconciles operational simplicity with robust analytical performance, presenting a compelling alternative to conventional instrumentation for antibiotic monitoring in resource-limited settings.
present study reports eco-friendly green synthesis approach fabrication of manganese oxide (MnO), iron oxide (Fe2O3), and manganese ferrite spinel (MnFe2O4) nanoparticles utilizing aqueous extract of Citrus sinensis (orange) peel as a natural reducing and capping agent. The phytochemicals present in the orange peel extract, including flavonoids, phenolic compounds, and ascorbic acid, served as effective bio-reductants for metal ion reduction and stabilization of the resulting nanoparticles. The synthesized nanoparticles were comprehensively characterized using multiple analytical techniques including X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDX), and vibrating sample magnetometry (VSM). XRD analysis confirmed the successful formation of crystalline phases with average crystallite sizes of 14.05 nm for MnO, 24.17 nm for alpha-Fe2O3(hematite), and 30.66 nm for MnFe(2)O(4 )spinel structure, calculated using the Debye-Scherrer equation. FESEM micrographs revealed predominantly spherical morphology with mean particle sizes of 19.65 +/- 3.35 nm, 24.29 +/- 1.48 nm, and 31.31 +/- 3.92 nm for MnO, Fe2O3, and MnFe2O4, respectively, as determined by Gaussian distribution analysis. EDX spectroscopy confirmed the elemental composition and stoichiometric ratios of the synthesized nanoparticles without significant impurities. VSM measurements revealed superparamagnetic behavior for MnFe(2)O(4 )nanoparticles, making them suitable for biomedical applications. The antibacterial efficacy was systematically evaluated against Gramnegative Escherichia coli (ATCC 25922) and Gram-positive Staphylococcus aureus (ATCC 25923) using the agar well diffusion method at varying concentrations (62.5-500 & micro;g/mL). Results demonstrated concentration-dependent antibacterial activity for all nanoparticles. Notably, MnFe(2)O(4 )nanoparticles exhibited superior antibacterial performance with maximum inhibition zones of 30 mm and 25 mm against E. coli and S. aureus at 500 & micro;g/mL, respectively. The enhanced antibacterial activity of the mixed metal oxide nanoparticles is attributed to synergistic effects of manganese and iron ions in generating reactive oxygen species (ROS) and disrupting bacterial cell membrane integrity. These findings suggest that green-synthesized MnFe(2)O(4 )nanoparticles hold significant potential for antimicrobial applications in biomedical and environmental sectors.
It's a sustainable and environmentally friendly method for reducing agricultural waste, while in the meantime it helps for the production of additional valuables. The production of ZnO nanoparticles by using green method employing four different Zahidi date palm (Phoenix dactylifera L.) residue aqueous extracts such as kernels, spines, leaflets and fibers are reported in the present investigation. The phytochemical content analyses of the prepared extracts show a variation in secondary metabolites for each extract and are discussed to find its role in the formation of nanoparticles and morphology. Kernels extract exhibited the highest total phenolic and flavonoid contents, while leaflet extract showed the highest saponin contents, and spines extract contained the highest alkaloid content. The prepared biosynthesized ZnO nanoparticles were characterized using UV-visible, FTIR, XRD, FESEM, and EDX techniques.Distinct ZnO morphologies were obtained depending on the residues used during synthesis. Kernels extract produced flower-like nanostructures, spines extract generated spherical nanoparticles, leaflet extract formed sheet-like structure, and fiber extract resulted in dense irregular nanostructures. Since all synthesis conditions were maintained constant, the variation in ZnO morphology was mainly attributed to residue-dependent phytochemical differences.
Water pollution caused by synthetic dyes continues to attract serious attention from environmental researchers, particularly because many of these compounds are toxic, non-biodegradable, and remain in aquatic systems for long periods of time. This study developed a nanocomposite hydrogel utilising graphene oxide and a copolymer of acrylic acid and maleic anhydride, designated as GO/P(AA-MA), through free radical polymerisation. Its efficacy as an adsorbent for Fuchsin Basic (FB), a cationic dye commonly used in the textile industry and biological staining, was assessed. Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and field-emission scanning electron microscopy (FESEM) were used to study the synthesised material. These tests showed that GO was successfully added to the polymer matrix and that the material had a rough, porous shape that was good for dye uptake. Batch experiments were conducted to investigate the influence of contact time, initial dye concentration, adsorbent mass, pH, ionic strength, and temperature on the adsorption behaviour. Kinetic data fitted the pseudo-second-order model very well (R2 > 0.99), while equilibrium data were best described by the Langmuir isotherm, giving a maximum monolayer capacity of about 285 mg g-1 at 298 K. Thermodynamic analysis indicated that the process is spontaneous, endothermic, and entropy-driven. The adsorbent was further tested over five adsorption-desorption cycles with only a modest loss of efficiency, which suggests that GO/P(AA-MA) is a promising and reusable material for the treatment of dye-contaminated water.
Polymer-based nanoparticles are colloidal systems composed of either natural or synthetic polymers. Bromocriptine, a semi-synthetic ergot alkaloid, binds to D2 dopamine receptors, decreasing prolactin secretion. It is prescribed for conditions like neuroleptic malignant syndrome, acromegaly, infertility, and hyperprolactinemia. Bromocriptine mesylate has limited water solubility, with gastrointestinal absorption between 28% and 37%. Nevertheless, its oral bioavailability is reduced to about 6% due to first-pass metabolism in the liver. This study aimed to develop and assess a polymeric nanoparticle system containing bromocriptine mesylate to improve its solubility, wettability, dissolution rate, and stability. This would facilitate more efficient delivery of bromocriptine mesylate through a fast-dissolving oral film. The method involved polymeric nanoparticle emulsification and solvent evaporation. Initially, the polymer solution was emulsified in an aqueous nanomaterial phase, then solvent evaporation was performed. PEG400 and poloxamer 188 served as the internal polymers, while Tween 80 functioned as the surfactant to produce the polymeric nanoparticles. The nanoparticle formulated with PEG400 as the internal polymer had a size range of 154 nm to 537 nm. The entrapment efficiency (EE) was tested on the selected formula (F4), which had the smallest particle size, resulting in 92%. Drug release reached 96% within 60 minutes. FTIR analysis showed no changes in the fingerprint region of bromocriptine
