title: Preparation and characterization of insulin nanoparticles using chitosan and its quaternized derivatives.
abstract: Insulin (INS), like other peptides, has low therapeutic activity when administered orally due to degradation by proteolytic enzymes. Polymeric nanoparticles have been introduced as a useful carrier for peptide oral delivery, because they can protect these compounds from degradation. The objective of the present study is to develop an INS nanoparticulate system by using chitosan (CS), triethylchitosan (TEC), and dimethyl-ethylchitosan (DMEC, a new quaternized derivative of CS). INS-polymer nanoparticles were prepared by the polyelectrolyte complexation method. The physicochemical properties of the nanoparticles including particle size distribution, zeta potential, and polydispersity index were determined by using dynamic light scattering technique. Transmission electron microscopy was also used to observe the morphology of the nanoparticles. The amount of INS loaded into the nanoparticles was determined by measuring the association efficiency and also the content of INS in the nanoparticles. In vitro release studies showed a relatively small burst effect at the beginning and then a sustained release characteristic for 5 hours.
authors.affiliation: Faculty of Pharmacy and Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Akbar
authors.initials: A
authors.lastname: Bayat
authors.forename: Bagher
authors.initials: B
authors.lastname: Larijani
authors.forename: Shahin
authors.initials: S
authors.lastname: Ahmadian
authors.forename: Hans E
authors.initials: HE
authors.lastname: Junginger
authors.forename: Morteza
authors.initials: M
authors.lastname: Rafiee-Tehrani
mesh_terms: D000284:Administration, Oral; D048271:Chitosan / Q000737:chemistry*; D003692:Delayed-Action Preparations / Q000008:administration & dosage / Q000737:chemistry*; D004058:Diffusion; D004339:Drug Compounding / Q000379:methods*; D007328:Insulin / Q000008:administration & dosage / Q000737:chemistry*; D008422:Materials Testing; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure
chemical_list: D003692:Delayed-Action Preparations; D007328:Insulin; D048271:Chitosan