Fabrication of Second Generation Smarter PLGA Based Nanocrystal Carriers for Improvement of Drug Delivery and Therapeutic Efficacy of Gliclazide in Type-2 Diabetes Rat Model

Drug delivery and therapeutic challenges of gliclazide, a BCS class II drug used in type 2 diabetes mellitus (T2DM) can be overcome by exploring smarter carriers of second-generation nanocrystals (SGNCs). A combined method of emulsion diffusion, high-pressure homogenization and solvent evaporation method were employed in the preparation of gliclazide loaded poly (D, L-lactide-co-glycolide) (PLGA) SGNCs. Taguchi experimental design was adopted in fabrication of Gliclazide SGNc using Gliclazide -PLGA ratio at 1:0.5, 1:0.75, 1:1 with stabilizer (Poloxamer-188, PEG 4000, HPMC E15 at 0.5, 0.75, 1% w/v). The formulated gliclazide of SGNCs were investigated for physicochemical properties, in vitro drug release, and in vivo performance studies using type-2 diabetes rat model. The formulation (SGNCF1) with Drug: PLGA 1: 0.5 ratio with 0.5% w/v Poloxamer-188 produced optimized gliclazide SGNCs. SGNCF1 showed spherical shape, small particle size (106.3 ± 2.69 nm), good zeta potential (-18.2 ± 1.30 mV), small PDI (0.222 ± 0.104) and high entrapment efficiency (86.27 ± 0.222%). The solubility, dissolution rate and bioavailability of gliclazide SGNCs were significantly improved compared to pure gliclazide. The findings emphasize gliclazide SGNCs produce faster release initially, followed by delayed release with improved bioavailability, facilitate efficient delivery of gliclazide in T2DM with better therapeutic effect.