Formation of self-assembled polyelectrolyte complex hydrogel derived from salecan and chitosan for sustained release of Vitamin C

Vitamin C (VC) is an indispensable nutrient for human health. However, poor chemical stability in gastric environment restricts its full assimilation by intestine. It is important to construct a safe carrier that can protect VC from the gastric fluid and sustainably release it in intestine. Herein, we designed a novel polyelectrolyte complex (PEC) hydrogel through self-assembly of salecan and chitosan. PEC structure formed by electrostatic interactions was confirmed by FT-IR, XRD, XPS and TGA. Their swelling, morphology, rheology, cytocompatibility and biodegradation were well investigated. In particular, VC released in a controlled and pH-dependent manner. The release amount in simulated intestinal fluid (SIF) was significantly higher than simulated gastric fluid (SGF), and can be maintained at high level in blood after 6 h. Release mechanism agreed well with Ritger-Peppas model. The purpose of this study was to develop a smart nutrient delivery platform for targeted release of VC in intestinal condition.