Controlled delivery of taxol from poly(ethylene glycol)-coated poly(lactic acid) microspheres.
The development of injectable microspheres for sustained drug delivery to the arterial wall is a major challenge. We demonstrated the possibility of entrapping an antiproliferative agent, taxol, in poly(ethylene glycol) (PEG)-coated biodegradable poly(lactic acid) (PLA) microspheres with a mean diameter of 2-6 microm. A solution of taxol and PLA dissolved in an acetone/dichloromethane mixture was poured into an aqueous solution of PEG [or poly(vinyl alcohol) (PVA] with stirring with a high-speed homogenizer for the formation of microspheres. Taxol recovery in PLA-PEG microspheres was higher (61.2 +/- 2.3%) than with PVA-based (41.6 +/- 1.8%) preparations. An analysis by diffuse reflectance infrared Fourier transform spectroscopy revealed that PEG was incorporated well on the PLA microsphere surface. Scanning electron microscopy revealed that the PEG-coated PLA microspheres were spherical in shape and had a smooth surface texture like those of PVA-based preparations. The amount of drug release was much higher initially (25-30%); this was followed by a constant slow-release profile for a 30-day period of study. This PEG-coated PLA microsphere formulation may have potential for the targeted delivery of antiproliferative agents to treat restenosis.
Das
G S
GS
Department of Cardiology, University of Minnesota, Minneapolis 55455, USA.
Rao GHR
Wilson
R F
RF
Chandy
T
T
D001672:Biocompatible Materials / Q000737:chemistry*; D007700:Kinetics; D007773:Lactates / Q000737:chemistry*; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D017239:Paclitaxel / Q000008:administration & dosage*; D011092:Polyethylene Glycols / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared
D001672:Biocompatible Materials; D007773:Lactates; C088513:poly(lactic acid-ethylene glycol); D011092:Polyethylene Glycols; D017239:Paclitaxel