Poly(trimethylene carbonate) and monomethoxy poly(ethylene glycol)-block-poly(trimethylene carbonate) nanoparticles for the controlled release of dexamethasone.
In this study, single emulsion and salting out methods were employed to prepare poly(trimethylene carbonate) (PTMC) and monomethoxy poly(ethylene glycol)-block-poly(trimethylene carbonate) (mPEG-PTMC) nanoparticles. Well-defined nanoparticles of a PTMC homopolymer were prepared using poly(vinyl alcohol) (PVA) as a stabilizer. The average size of the nanoparticles can be adjusted by varying the stirring speed and polymer concentration. These particles can be readily freeze-dried and redispersed, with little influence on the average particle size and size distribution. Nanoparticles based on amphiphilic mPEG-PTMC can be prepared without an additional stabilizer. In this case, the size of the obtained nanoparticles did not vary much and ranged between 95 and 120 nm. These nanoparticles could be freeze-dried and redispersed as well. Using the salting out method, dexamethasone was loaded into PTMC and mPEG-PTMC nanoparticles at a highest efficiency of respectively 54% and 88%. With the single emulsion method, the loading efficiencies were, respectively, 91% and 72%. These drug-loaded particles were stable in time for at least 20 weeks. It was found that the release of dexamethasone from these nanoparticles was diffusion-controlled and could be sustained for 14 to 60 days. Depending on the nature of the polymer employed and the preparation method, dexamethasone diffusion coefficients varied between 4.8 x 10(-18) and 22.6 x 10(-18) cm(2)/s.
Zhang
Zheng
Z
Institute for Biomedical Technology (BMTI) and Department of Polymer Chemistry and Biomaterials, Faculty of Science and Technology, University of Twente, P.O. Box 217, 7500 Enschede, The Netherlands.
Grijpma
Dirk W
DW
Feijen
Jan
J
D000893:Anti-Inflammatory Agents / Q000008:administration & dosage*; D003692:Delayed-Action Preparations; D003907:Dexamethasone / Q000008:administration & dosage*; D004058:Diffusion; D004146:Dioxanes; D004337:Drug Carriers / Q000737:chemistry*; D004355:Drug Stability; D053758:Nanoparticles; D011092:Polyethylene Glycols; D011108:Polymers; D013678:Technology, Pharmaceutical
D000893:Anti-Inflammatory Agents; D003692:Delayed-Action Preparations; D004146:Dioxanes; D004337:Drug Carriers; D011108:Polymers; C515872:monomethoxy poly(ethylene glycol)-block-poly(trimethylene carbonate); C059299:polytrimethylene carbonate; D011092:Polyethylene Glycols; D003907:Dexamethasone; C028210:monomethoxypolyethylene glycol