Formulation and Optimization of Selenium Nanoparticles Using <i>Passiflora edulis</i> Leaf Extract: Permeation and in Vitro Release Kinetic Study

Passiflora edulis-selenium nanoparticles (PE-SeNPs) were formulated using a green synthesis method and evaluated for their solubility, antimicrobial effects, antioxidant effects, permeation, and kinetic release. These formulations were optimized using the Box-Behnken design, investigating the effects of the concentration of PE extract (1-5 mL), sodium selenite (10-30 mL), and chitosan (1 mg/mL) on the dependent variables, for example, PE-SeNPs' percentage yield and solubility of PE-SeNPs. Fourteen formulations were prepared by varying these concentrations and were analyzed by ultraviolet-visible, Fourier-transform infrared, and scanning electron microscopy. The average size of PE-SeNPs ranged from 154 to 198 nm. The optimized formula was found to be the concentration of PE extract (4.6 mL), Na₂SeO₃ (29.7 mL), and chitosan (1.7 mg/mL). The antioxidant activity was evaluated, and the average percentage inhibition of synthesized PE-SeNPs and PE extract was found to be 64% and 58%, respectively. PE-SeNPs' permeability coefficient of PE-SeNPs was 0.473 cm/h, followed by zero-order kinetics. Both PE extract and PE-SeNPs showed antibacterial activity against Escherichia coli and Bacillus subtilis however, PE-SeNPs were more effective.