Table 5.

Polymer carrier systems. Commonly used polymers for construction of nanoparticles, their biocompatibility and use in peptide delivery.

Polymer	Biocompatibility†	Example of use	Ref.
PLA	Biocompatible and biodegradable	BSA loaded with 71 % efficiency, BSA was stable after release	[114]
PCL	Degraded by hydrolysis	Preparation of long-term implantable device Insulin loaded with 96% efficiency, improved response to OGTT Has mucoadhesive properties AmB loaded PCL nanoparticles two- to three-times more effective than free AmB	[115,116]
Chitosan	Nontoxic, biocompatible	Insulin-loaded chitosan nanoparticles enhanced intestinal absorption of insulin through a combination of insulin internalization in enterocytes and insulin-loaded particle uptake by Peyer's patches	[117]
Gelatin	Nontoxic, biodegradable	Encapsulated paclitaxel, oligonucleotides, chloroquine	[118–120]
Poly(alkyl-cyano-acrylates)	Biodegradable and biocompatible, degraded by esterases. Produce some toxic metabolites, not suitable for human use	Encapsulated doxorubicin, ampicillin, indomethacin	[111]
PLGA	Biodegradable, excellent toxicological profile	PLGA nanoparticles with influenza HA incorporated throughout the matrix, increased uptake via M cells	[121]

^†Data taken from [111].

AmB: Amphotericin B; BSA: Bovine serum albumin; HA: Hemagglutinin; OGTT: Oral glucose tolerance test; PCL: Poly(ε-caprolactone) PLA: Poly(lactic acid); PLGA: Poly(lactic-co-glyclic acid).