Polyelectrolyte Complex-Based Ionically Gelled Biopolymeric Systems for Sustained Drug Release

Abstract

The therapeutic agents such as proteins, peptides, or even cells are generally not stable at extreme conditions prevailing in the gastrointestinal tract. An ideal drug delivery system should protect the drugs from unfriendly environments and deliver them at the specific site, at the desired rate and in appropriate dosage forms [1, 2, 3]. For example, oral drug delivery systems must be designed in such a way that the drug carrier has good resistance against gastrointestinal enzymes and pH gradients (i.e., from 1 to 3 in the stomach to 6 to 7 in the intestine) [4]. The choice of the drug carrier to meet these requirements is critical in the design of drug delivery systems. Various polymeric substances can be used as a drug career. Use of natural polysaccharides is gaining attraction recently, as they are biodegradable, biocompatible, and less toxic. Apart from this, natural polysaccharides are amenable to simple modifications through which their properties can be fine-tuned to meet the specific requirements for a given therapeutic application; they can absorb drug molecules more efficiently and release them at a controlled rate. Polysaccharides from various natural sources such as algal sources (e.g., alginate), plant source (e.g., pectin, guar gum), microbial origin (e.g., cellulose, dextran, pullulan, levan, xanthan gum, gellan gum, etc.), and animal orgin (e.g., chitin, chitosan) are employed in drug delivery applications includes.