Biomimetics in drug delivery systems: A critical review.

Today, the advanced drug delivery systems have been focused on targeted drug delivery fields. The novel drug delivery is involved with the improvement of the capacity of drug loading in drug carriers, cellular uptake of drug carriers, and the sustained release of drugs within target cells. In this review, six groups of therapeutic drug carriers including biomimetic hydrogels, biomimetic micelles, biomimetic liposomes, biomimetic dendrimers, biomimetic polymeric carriers and biomimetic nanostructures, are studied.

Effect of molecular mass of methoxypoly(ethylene glycol) activated with succinimidyl carbonate on camouflaging pancreatic islets.

The surface modification of Langerhans islets by grafting activated poly(ethylene glycol) on to their capsules in order to prevent immune-system stimulation is a novel method in diabetes cell therapy. In the present study, mPEG [methoxypoly(ethylene glycol)] with two molecular masses of 5 and 10 kDa, activated with SC (succinimidyl carbonate), was grafted on to the surface of pancreatic islets at a polymer concentration of 22 mg/ml. It was found that PEGylated islets were viable and active, and no morphological changes on the collagen capsule of islets were observed.

Effect of polymer concentration on camouflaging of pancreatic islets with mPEG-succinimidyl carbonate.

Modifying the surface of living cells with specially selected polymers is a new method of protecting them from the immune system. Covalent attachment of polyethylene glycol (PEG) derivatives on the capsule of pancreatic islets in aqueous media under moderate conditions is an example. This study aimed to find out whether higher polymer concentration could protect PEGylated islets from immune systems more efficiently without affecting their viability and morphology.