Insulin encapsulation, stability and release from poly(lactide-co-glycolide) microspheres: effect of the co-encapsulatin of different surfactants

摘要

Microspheres are certainly the most diffused system for the delivery of proteins and peptides. Among therapeutically active peptides, insulin is of great interest for its wide use in the treatment of diabetes mellitus. Asides from beign the target of proteolytic enzymes in the body, insulin is susceptible to chemical and physical degradation in both solution and suspension~1. However, the addition of block copolymers of polyethylen-polypropylenglycols such as Pluronics and polysorbate based surfactant such as Tweens has been shown to successfully stabilise insulin in solution~2. On the other hand, the use of surfactants has shwon to increase peptide/protein stability within microspheres and optimise the distribution of protein~3.