ABSTRACT
Peptide-Delivery System ....................................................................................................... 173 7.4.1 Synthetic Biodegradable Polymeric Nano/Microparticles ........................................ 175 7.4.2 Nonbiodegradable Synthetic Polymers...................................................................... 179 7.4.3 Natural and Protein-Based Polymers for Oral Peptide Delivery .............................. 182
7.4.3.1 Protein-Based Polymers for Oral Protein Delivery .................................... 183 7.4.4 Preparation of Nano/Microparticles .......................................................................... 183
7.4.4.1 Nano/Microparticles Obtained by Polymerization of Monomers ............................................................................................... 184
7.4.4.2 Particles from Preformed Polymers ............................................................ 186 7.5 Concluding Remarks ............................................................................................................. 187 References ...................................................................................................................................... 187
Recent advancement in the eld of pharmaceutical biotechnology and introduction of recombinant DNA technology have led to the production of a number of therapeutic peptides and proteins for the treatment of several life-threatening diseases (Table 7.1). A number of peptide-based therapeutics such as recombinant hormones, cytokines, vaccines, monoclonal antibodies, therapeutic enzymes, and the like have been recently approved for clinical use [1]. However, most of these peptides are administrated by parenteral route. Inherent short half-lives of peptides and chronic therapy requirements in a majority of cases make their repetitive dosing necessary [2]. Frequent injections, oscillating blood drug concentrations, and low patient acceptability make even the simple parenteral administration of these drugs problematic [3,4]. In spite of signi cant advancement in the eld of pharmaceutical research, development of a proper noninvasive delivery system for peptides remains a distant reality. Although there have been reports of successful delivery of various peptide therapeutics across nonoral mucosal routes (such as nasal and buccal), the oral route continues to be the most preferred route for drug administration [5-7]. The oral route, despite enormous barriers that exist in the gastrointestinal tract (GIT), has obvious advantages such as ease of administration, patient compliance, and cost effectiveness [8,9].
