title: Use of hydrodynamic flow focusing for the generation of biodegradable camptothecin-loaded polymer microspheres.
abstract: The present study was conducted to investigate the use of hydrodynamic flow focusing for the generation of biodegradable polymer microspheres encapsulating the anticancer drug camptothecin. Poly(D,L-lactide-co-glycolide) (PLGA) and poly(L-lactide) (PLA) were used as the matrix materials. Camptothecin was dissolved in the disperse phase and microspheres with a mean size between 2 and 3 microm generated using hydrodynamic flow focusing. When up to 1 wt.% of the drug was added to PLA, the drug encapsulation efficiency was 64%. For PLGA, the drug encapsulation efficiency was between 39 and 46%. Drug release from PLA particles was rapid and complete within 6 h, while drug release from PLGA particles showed no burst effect and followed a first order release profile. The encapsulated camptothecin stayed in its active lactone form, as shown by HPLC, and was able to exert cell toxic effects as shown by a cell viability assay. Hydrodynamic flow focusing is a promising tool for the preparation of drug-releasing biodegradable microspheres typically made by solvent evaporation and/or solvent extraction, as indicated by the successful encapsulation of the anticancer drug camptothecin.
authors.affiliation: Division of Pharmaceutics and Biopharmaceutics, Faculty of Pharmaceutical Sciences, The University of British Columbia, 2146 East Mall, Vancouver, BC V6T1Z3, Canada.
authors.forename: Thomas
authors.initials: T
authors.lastname: Schneider
authors.forename: Hong
authors.initials: H
authors.lastname: Zhao
authors.forename: John K
authors.initials: JK
authors.lastname: Jackson
authors.forename: Glenn H
authors.initials: GH
authors.lastname: Chapman
authors.forename: James
authors.initials: J
authors.lastname: Dykes
authors.forename: Urs O
authors.initials: UO
authors.lastname: Häfeli
mesh_terms: D002166:Camptothecin / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D019344:Lactic Acid / Q000737:chemistry*; D008863:Microspheres; D011091:Polyesters / Q000737:chemistry*; D011100:Polyglycolic Acid / Q000737:chemistry*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer
chemical_list: D011091:Polyesters; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; C033616:poly(lactide); D002166:Camptothecin