Chitosan-Coated silver nanoparticles with various floral honey bioreductors: A promising nonalcoholic hand gel sanitizer formulation

• Green-synthesis of AgNPs using various reducing agents derived from floral honey of Ceiba pentandra, Nephelium lappaceum, Hevea brasiliensis, and Coffea spp. • Coating of AgNPs with oligochitosan obtained from depolymerized low molecular weight chitosan. • Evaluation of the antibacterial activity, toxicity, stability, and safety of AgNPs-Chitosan as an active ingredient in the formulation of a non-alcoholic hand sanitizer. Antimicrobial resistance represents a critical global health challenge, necessitating innovative strategies to combat resistant pathogens. In this study, silver nanoparticles (AgNPs) were synthesized using honey as a bioreductant and coated with oligochitosan derived from the depolymerization of low-molecular-weight chitosan. The synthesis employed eco-friendly methods, with characterization performed via UV–Vis spectroscopy, FTIR, TEM, EDX, XRD, and LC HRMS. AgNPs synthesized with Ceiba pentandra honey exhibited an average particle size of 11.71 nm, demonstrating high antibacterial activity when coated with oligochitosan. The 10 % AgNPs-Chitosan-based hand gel sanitizer formulation achieved inhibition zones of 14.84 ± 0.40 mm against Staphylococcus aureus and 11.16 ± 0.73 mm against Pseudomonas aeruginosa. The hand gel sanitizer formulation exhibited stable pH (4.0–4.3), high resistance to syneresis at 5 °C and 40 °C, and superior antibacterial efficacy compared to alcohol-based hand gel sanitizers. Dermatological assessments confirmed the formulation's safety, and Artemia salina toxicity tests revealed the highest LC 50 value (2,648.97 ppm) for AgNPs derived from C. pentandra honey. This work provides an eco-friendly, efficient method for AgNP synthesis with strong potential for biomedical and environmental applications, including their use in hand gel sanitizers to reduce pathogen transmission in various settings, contributing to the advancement of green nanotechnology.