title: Morphology control of polylactide microspheres enclosing irinotecan hydrochloride with polylactide based polymer surfactant for reduction of initial burst.
abstract: We introduced newly biodegradable polymer surfactant to poly(D,L-lactide) microspheres for exhibiting precisely controlled release rate of antitumor agent. We newly designed biodegradable polymer surfactant, poly(ethyleneoxide monooleate)-block-poly(D,L-lactide); (MOPEO-PLA), which has a biocompatible, oil-soluble and compatible with polylactide matrices. Polylactide (PLA) microspheres with MOPEO-PLA enclosing Irinotecan hydrochloride (CPT-11) was successfully fabricated by solvent evaporation method via O/O emulsion. The surface morphology was strongly affected to MOPEO-PLA content in PLA microspheres; the wrinkles on microsphere surface were decreased with increasing MOPEO-PLA content. It was found from DSC scans that Tg of PLA drastically decreased with introducing MOPEO-PLA, indicating that MOPEO-PLA miscible with PLA. MOPEO-PLA, played as a plasticizer, made the surface smoothed. The rate of release in a short duration was minimum value at adding 20 wt.% of MOPEO-PLA. This result was due to the smaller surface area of PLA microspheres with smoothed surface.
authors.affiliation: Department of Chemical Engineering, Nara National College of Technology, 22 Yata, Yamatokoriyama, Nara 639-1080, Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Nishino
authors.forename: Akio
authors.initials: A
authors.lastname: Kishida
authors.forename: Hidekazu
authors.initials: H
authors.lastname: Yoshizawa
mesh_terms: D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000737:chemistry; D002152:Calorimetry, Differential Scanning; D002166:Camptothecin / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000737:chemistry; D003692:Delayed-Action Preparations; D016503:Drug Delivery Systems; D000077146:Irinotecan; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D011091:Polyesters / Q000138:chemical synthesis / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000138:chemical synthesis / Q000737:chemistry*
chemical_list: D000970:Antineoplastic Agents; D003692:Delayed-Action Preparations; D011091:Polyesters; C507885:poly(ethylene oxide monooleate-block-DL-lactide); D011092:Polyethylene Glycols; C033616:poly(lactide); D000077146:Irinotecan; D002166:Camptothecin