Green synthesis and optimization of Carissa carandas Linn. Silver nanoparticles for diabetic treatment

Background: Green synthesis of silver nanoparticles (AgNPs) using medicinal plants has emerged as a promising, eco-friendly approach for therapeutic nanoparticle development. Carissa carandas L., traditionally known for its antidiabetic properties, was selected for the biosynthesis of AgNPs and subsequent in-vitro evaluation Methods: Aqueous root extract of Carissa carandas was used to synthesize AgNPs via microwave-assisted reduction of silver nitrate. The synthesis was optimized using Taguchi design (L9 orthogonal array). Nanoparticles were characterized using UV-Vis spectroscopy, FTIR, SEM, particle size analysis, and zeta potential measurements. Drug content and release were assessed via UV-spectroscopy, and kinetic modeling was performed. Antidiabetic activity was evaluated using an α-amylase inhibition assay, with Acarbose as the standard. Results: Phytochemical screening confirmed the presence of flavonoids, phenols, and glycosides contributing to AgNP formation. Optimized nanoparticles exhibited spherical morphology, average particle size of ~684.9 nm (DLS), zeta potential of –17.8 mV, and strong SPR at 435 nm. Drug entrapment ranged from 80–83%, and formulation F9 showed sustained release (86.3% at 24 hours). Kinetic modeling indicated Higuchi and first-order release profiles. AgNPs demonstrated dose-dependent α-amylase inhibition (up to 72.73% at 800 µg/mL), comparable to Acarbose (77.19%). Conclusion: Green-synthesized AgNPs from Carissa carandas root extract showed good antidiabetic potential and sustained drug release, supporting their use in natural diabetes management. Keywords: Carissa carandas, silver nanoparticles, green synthesis, microwave irradiation, drug release, α-amylase inhibition, antidiabetic activity