Development and in vitro characterization of insulin loaded whey protein and alginate microparticles

• Published in: International journal of pharmaceutics Vol. 439; no. 1-2; pp. 136 - 144
• Main Authors: Déat-Lainé, Emmanuelle, Hoffart, Valérie, Cardot, Jean-Michel, Subirade, Muriel, Beyssac, Eric
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 15-12-2012
• Subjects: Alginate; Alginates - chemistry; calcium; Calcium - analysis; Chymotrypsin - chemistry; cold; encapsulation; enzyme inhibition; extrusion; gelation; Glucuronic Acid - chemistry; Hexuronic Acids - chemistry; Hydrogen-Ion Concentration; Insulin; Insulin - chemistry; ions; Microparticle; Milk Proteins - chemistry; Oral administration; Particle Size; trypsin; Trypsin - chemistry; viscosity; Whey protein; Whey Proteins; Microparticle; Alginate; Whey protein; Insulin; Oral administration
• ISSN: 0378-5173; 1873-3476
• DOI: 10.1016/j.ijpharm.2012.10.003

Insulin was encapsulated into microparticles (MP) made of denaturized whey proteins (WP) and alginate (ALG) using an extrusion/cold gelation process with calcium ions. High encapsulation efficiency of 85% was obtained. Influence of insulin on polymeric viscosity and on microparticle behavior was evaluated. Insulin seemed to interact with WP chains by non covalent binding and steric hindrance. This influence was balanced by ALG addition. Nevertheless, insulin was released rapidly by diffusion at both acidic and intestinal dissolution media. Despite this fast in vitro release, WP/ALG MP showed an important enzymatic inhibition effect on trypsin and alpha-chymotrypsin. Thus, WP/ALG MP contributed to an effective insulin protection towards enzymatic degradation. The aforementioned results suggested that WP based microparticles are a promising carrier for improving oral delivery of insulin.