title: Incorporation methods for cholic acid chitosan-g-mPEG self-assembly micellar system containing camptothecin.
abstract: A water-insoluble anticancer agent, camptothecin (CPT) was incorporated to a polymeric micelle carrier system preparing from cholic acid chitosan-grafted poly (ethylene glycol) methyl ether (CS-mPEG-CA). CS-mPEG-CA formed a core-shell micellar structure with a critical micelle concentration (CMC) of 7.08 microg/ml. Incorporation efficiency was investigated by varying physical incorporation method and initial drug loading. Among three incorporation methods (dialysis, emulsion and evaporation methods), an emulsion method showed the highest CPT incorporation efficiency. Increasing the initial CPT loading from 5 to 40%, the incorporation efficiency decreased. In all examined CPT-loaded CS-mPEG-CA micelles, 5% initial drug loading showed the highest drug incorporation efficiency. Release of CPT from the micelles was sustained when increasing the initial CPT loading. This indicates the importance of incorporation method and the initial drug loading to obtain the optimum particle size with high drug loading and sustained drug release. When compared to the unprotected CPT, CPT-loaded CS-mPEG-CA micelles were able to prevent the hydrolysis of the lactone group of the drug. This novel CS-mPEG-CA polymer presents considerable potential interest in the further development of CPT carrier.
authors.affiliation: Nanotechnology for Drug/Gene Delivery Systems Group, Faculty of Pharmacy, Silpakorn University, Nakhon Pathom 73000, Thailand.
authors.forename: Tanasait
authors.initials: T
authors.lastname: Ngawhirunpat
authors.forename: Nanthida
authors.initials: N
authors.lastname: Wonglertnirant
authors.forename: Praneet
authors.initials: P
authors.lastname: Opanasopit
authors.forename: Uracha
authors.initials: U
authors.lastname: Ruktanonchai
authors.forename: Rangrong
authors.initials: R
authors.lastname: Yoksan
authors.forename: Kaewkarn
authors.initials: K
authors.lastname: Wasanasuk
authors.forename: Suwabun
authors.initials: S
authors.lastname: Chirachanchai
mesh_terms: D002166:Camptothecin / Q000737:chemistry / Q000494:pharmacology*; D048271:Chitosan / Q000737:chemistry*; D019826:Cholic Acid / Q000737:chemistry*; D016503:Drug Delivery Systems / Q000379:methods*; D006207:Half-Life; D006863:Hydrogen-Ion Concentration / Q000187:drug effects; D006868:Hydrolysis / Q000187:drug effects; D007700:Kinetics; D007783:Lactones / Q000737:chemistry; D008738:Methyl Ethers / Q000737:chemistry*; D008823:Micelles; D046529:Microscopy, Electron, Transmission; D010316:Particle Size; D011092:Polyethylene Glycols / Q000737:chemistry*
chemical_list: D007783:Lactones; D008738:Methyl Ethers; D008823:Micelles; D011092:Polyethylene Glycols; D048271:Chitosan; D019826:Cholic Acid; D002166:Camptothecin