Formulation and Optimization of Polymeric Nanoparticles for Intranasal Delivery of Lorazepam Using Box-Behnken Design:In VitroandIn VivoEvaluation
The aim of the present study was to optimize lorazepam loaded PLGA nanoparticles (Lzp-PLGA-NPs) by investigating the effect of process variables on the response using Box-Behnken design. Effect of four independent factors, that is, polymer, surfactant, drug, and aqueous/organic ratio, was studied on two dependent responses, that is,z-average and % drug entrapment. Lzp-PLGA-NPs were successfully developed by nanoprecipitation method using PLGA as polymer, poloxamer as surfactant and acetone as organic phase. NPs were characterized for particle size, zeta potential, % drug entrapment, drug release behavior, TEM, and cell viability. Lzp-PLGA-NPs were characterized for drug polymer interaction using FTIR. The developed NPs showed nearly spherical shape withz-average 167–318 d·nm, PDI below 0.441, and −18.4 mV zeta potential with maximum % drug entrapment of 90.1%.In vitrodrug release behavior followed Korsmeyer-Peppas model and showed initial burst release of21.7±1.3%with prolonged drug release of69.5±0.8%from optimized NPs up to 24 h.In vitrodrug release data was found in agreement withex vivopermeation data through sheep nasal mucosa.In vitrocell viability study on Vero cell line confirmed the safety of optimized NPs. Optimized Lzp-PLGA-NPs were radiolabelled with Technitium-99m for scintigraphy imaging and biodistribution studies in Sprague-Dawley rats to establish nose-to-brain pathway.