title: Research on thymopentin loaded oral N-trimethyl chitosan nanoparticles.
abstract: Peptides, although high efficacy and specificity in their physiological function, usually have low therapeutical activities due to their poor bioavailability when administrated orally. Nanoparticles have been regarded as a useful vector for targeted drug delivery system because they can protect drug from being degraded quickly and pass the gastrointestinal barriers. Here we described a novel oral N-trimethyl chitosan nanoparticles formulation containing thymopentin (Tp5-TMC-NP). N-trimethyl chitosan (TMC) was synthesized and then used to prepare Tp5-TMC-NP by ionotropic gelation. A three-factor, five-level CCD (Central Composite Design) design was used in the optimization procedure, with HPLC as the analyzing method. The resulting Tp5-TMC-NP had a regular spherical surface and a narrow particle size range with a mean diameter of 110.6 nm. The average entrapment efficiency was 78.8%. The lyophilized Tp5-TMC-NP formulation was stable in 4 degrees C or -20 degrees C after storage of 3 months without obvious changes in morphology, particle size, pH and entrapment ratio. The results of the flow cytometer determination showed that the ratio of CD4+/CD8+ of Wistar female rat givenTp5-TMC-NP (ig) was 2.59 time that of the group given Tp5 (ig).
authors.affiliation: West China School of Pharmacy, Sichuan University, No. 17, Section 3, Renmin South Road, Chengdu 610041, China.
authors.forename: Xiao-jia
authors.initials: XJ
authors.lastname: Yuan
authors.forename: Zhi-rong
authors.initials: ZR
authors.lastname: Zhang
authors.forename: Qing-guo
authors.initials: QG
authors.lastname: Song
authors.forename: Qin
authors.initials: Q
authors.lastname: He
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage* / Q000494:pharmacology*; D000465:Algorithms; D048271:Chitosan; D004339:Drug Compounding; D005079:Excipients; D005434:Flow Cytometry; D005612:Freeze Drying; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles; D010316:Particle Size; D016305:Thymopentin / Q000008:administration & dosage* / Q000494:pharmacology*
chemical_list: D000276:Adjuvants, Immunologic; D005079:Excipients; D007202:Indicators and Reagents; D048271:Chitosan; D016305:Thymopentin