The reproductive health of women is governed by an optimal balance in the host–microbiota interaction. Depletion of the beneficial vaginal microflora caused by depletion of Lactobacillus species and increased proliferation of pathogens results in gynaecological infections. Among women of reproductive age, vaginal infections are increasingly prevalent. Attaining therapeutic efficacy using conventional formulations remains a challenge as vaginal fluids quickly remove or dilute the therapeutic formulations. Hydrogels have been widely exploited for targeted delivery of therapeutics directly into the vaginal mucus. With a careful choice of polymers (natural, synthetic, or semisynthetic), hydrogels with specific properties, such as stimuli responsiveness, antimicrobial, and muco-adhesiveness, can be tailored for higher therapeutic efficacy. In this review, the advances in hydrogel strategies for the treatment of vaginal infections are presented with emphasis on the types and properties that play a significant role in vaginal drug delivery systems.

In this work, stable and spherical silver nanoparticles (AgNPs) were synthesized in situ from silver salt (silver nitrate) using the aqueous extract of the okra plant (Abelmoschus esculentus) at room temperature and ambient pH conditions. The influences of different parts of the plant (such as the leaves, stems, and pods) on the chemical-reducing effectiveness of silver nitrate to silver nanoparticles were investigated. The aqueous extract of the leaves was found to be more effective in the chemical reduction of silver nanoparticles and in stabilizing them at the same time. The silver nanoparticles produced were stable and did not precipitate even after storage for 1 month. The extract of the stem was less effective in the reduction capacity followed by the extract of the pods. The results indicate that the different amounts of phytochemicals present in the leaves, stems, and pods of the okra plant are responsible for the chemical reduction and stabilizing effect. The silver nanoparticles were characterized by UV-Vis spectroscopy, Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDX). The surface plasmon resonance (SPR) peak at 460 nm confirmed the formation of silver nanoparticles. The nanoparticles were spherical with an average size of 16 nm and polycrystalline with face-centered cubic (fcc) structures. The z-scan technique was used to study the nonlinear refraction and absorption coefficients of AgNPs at wavelengths of 488 and 514 nm under C.W. mode excitation. The nonlinear refraction index and nonlinear absorption coefficients were calculated in the theoretical equations in the experimental data. The antibacterial properties of the nanoparticles were evaluated against Gram-positive and Gram-negative bacteria.

The wildfire-like spread of COVID-19, caused by severe acute respiratory syndrome-associated coronavirus-2, has resulted in a pandemic that has put unprecedented stress on the world’s healthcare systems and caused varying severities of socio-economic damage. As there are no specific treatments to combat the virus, current approaches to overcome the crisis have mainly revolved around vaccination efforts, preventing human-to-human transmission through enforcement of lockdowns and repurposing of drugs. To efficiently facilitate the measures implemented by governments, rapid and accurate diagnosis of the disease is vital. Reverse-transcription polymerase chain reaction and computed tomography have been the standard procedures to diagnose and evaluate COVID-19. However, disadvantages, including the necessity of specialized equipment and trained personnel, the high financial cost of operation and the emergence of false negatives, have hindered their application in high-demand and resource-limited sites. Nanoparticle-based methods of diagnosis have been previously reported to provide precise results within short periods of time. Such methods have been studied in previous outbreaks of coronaviruses, including severe acute respiratory syndrome-associated coronavirus and middle east respiratory syndrome coronavirus. Given the need for rapid diagnostic techniques, this review discusses nanoparticle use in detecting the aforementioned coronaviruses and the recent severe acute respiratory syndrome-associated coronavirus-2 to highlight approaches that could potentially be used during the COVID-19 pandemic.

Alginate, a naturally occurring polysaccharide derived from brown algae, has emerged as a versatile cornerstone in the field of biomedical materials. Its widespread adoption is driven by its exceptional biocompatibility and the unique cation-dependent gelation defined by the “egg-box” model. This review examines the fundamental chemistry of alginate, detailing how its crosslinking mechanisms dictate the physicochemical properties essential for clinical performance. The discussion bridges the gap between polymer structure and diverse biomedical applications, including drug delivery, tissue engineering, and the clinical management of gastrointestinal reflux and wound care. Furthermore, the article evaluates the role of alginate-based systems in the biomedical and metabolic management of obesity and diabetes. By analyzing how alginate influences satiety, glycemic index modulation, and lipid absorption through biophysical mechanisms, this review highlights the transition from fundamental chemical architecture to practical clinical utility. By integrating structural chemistry with physiological impact, this work underscores the evolving potential of alginate-based materials as supportive and functional strategies in modern clinical care.

Well-defined and stable, spherical silver nanoparticles (AgNPs) were synthesized at room temperature by a green approach using xanthan gum (XG) as a reducing and stabilizing agent. The effect of various concentrations of silver nitrate on the formation kinetics of AgNPs at 23 °C and pH 10 was studied. The nanoparticles formation with XG as a reducing agent followed a first-order reaction kinetics. The denaturation of XG from a helix to a random polymer coil was achieved at 23 °C and pH 10. Renaturation of XG was not observed at room temperature, and the nanoparticles were stable against aggregation during prolonged storage of more than 8 months. The formation of AgNPs was studied using UV-Vis absorption spectroscopy, and a strong surface plasmon resonance peak centred around 407–413 nm confirmed the presence of nanoparticles. The optical bandgap of the nanoparticles was estimated to be in the range of 2.46 to 2.55 eV. Transmission electron microscope (TEM) images showed spherical and non-agglomerated nanoparticles of 10–22 nm size range. The Fourier-transform infra-red spectroscopy (FTIR) revealed the presence of an organic layer (due to XG) on the surface of the nanoparticles. The nanoparticles were highly effective in the degradation of a model organic pollutant, 2-nitrophenol, exhibiting 80% degradation within 10 min, with a pseudo-first-order rate constant of 0.211 min ^− 1 . The AgNPs showed size-dependent favourable antibacterial potential against Staphylococcus aureus and Salmonella typhimurium .

Alginate-silver nanocomposites in the form of spherical beads and films were prepared using a green approach by using the aqueous extract of Ajwa date seeds. The nanocomposites were fabricated by in situ reduction and gelation by ionotropic crosslinking using calcium ions in solution. The rich phytochemicals of the date seed extract played a dual role as a reducing and stabilizing agent in the synthesis of silver nanoparticles. The formation of silver nanoparticles was studied using UV-Vis absorption spectroscopy, and a distinct surface plasmon resonance peak at 421 nm characteristic of silver nanoparticles confirmed the green synthesis of silver nanoparticles. The morphology of the nanocomposite beads and film was compact, with an even distribution of silver nanoclusters. The catalytic property of the nanocomposite beads was evaluated for the degradation of 2-nitrophenol in the presence of sodium borohydride. The degradation followed pseudo-first-order kinetics with a rate constant of 1.40 × 10−3 s−1 at 23 ℃ and an activation energy of 18.45 kJ mol−1. The thermodynamic parameters, such as changes in enthalpy and entropy, were evaluated to be 15.22 kJ mol−1 and −197.50 J mol−1 K−1, respectively. The nanocomposite exhibited properties against three clinically important pathogens (gram-positive and gram-negative bacteria).