Chitosan/guar gum-based thermoreversible hydrogels loaded with pullulan nanoparticles for enhanced nose-to-brain drug delivery.

The biopolymers-based two-fold system could provide a sustained release platform for drug delivery to the brain resisting the mucociliary clearance, enzymatic degradation, bypassing the first-pass hepatic metabolism, and BBB thus providing superior bioavailability through intranasal administration. In this study, poloxamers PF-127/PF-68 grafted chitosan HCl-co-guar gum-based thermoresponsive hydrogel loaded with eletriptan hydrobromide laden pullulan nanoparticles was synthesized and subjected to dynamic light scattering, Fourier transform infrared spectroscopy, thermal analysis, x-ray diffraction, scanning electron microscopy, stability studies, mucoadhesive strength and time, gel strength, cloud point assessment, rheological assessment, ex-vivo permeation, cell viability assay, histology studies, and in-vivo Pharmacokinetics studies, etc. It is quite evident that CSG-EH-NPs T-Hgel has an enhanced sustained release drug profile where approximately 86 % and 84 % of drug released in phosphate buffer saline and simulated nasal fluid respectively throughout 48 h compared to EH-NPs where 99.44 % and 97.53 % of the drug was released in PBS and SNF for 8 h. In-vivo PKa parameters i.e., mean residence time (MRT) of 11.9 ± 0.83 compared to EH-NPs MRT of 10.2 ± 0.92 and area under the curve (AUC) of 42,540.5 ± 5314.14 comparing to AUC of EH-NPs 38,026 ± 6343.1 also establish the superiority of CSG-EH-NPs T-Hgel.