Related Experiment Video
Updated: Aug 11, 2026

Preparation and Characterization of Individual and Multi-drug Loaded Physically Entrapped Polymeric Micelles
Published on: August 28, 2015
Novel drug release profiles from micellar solutions of PLA-PEO-PLA triblock copolymers
Sarvesh K Agrawal1, Naomi Sanabria-DeLong, Jeannine M Coburn
1Department of Chemical Engineering, University of Massachusetts, Amherst, 686 North Pleasant Street, Amherst, MA 01003, United States.
Abstract:
We have achieved nearly zero order sustained release behavior for periods up to 10-20 days for two hydrophobic drugs, sulindac and tetracaine, from 5wt.% micellar solutions of poly(lactide)-poly(ethylene oxide)-poly(lactide) (PLA-PEO-PLA) triblock copolymer. The effect of PLA block length and crystallinity on the drug release profiles was studied. A series of polymers with constant PEO molecular weight of 8900Da and PLA molecular weight varying in the range of 4100-6500Da were examined. Drug release was found to be much faster for polymers with crystalline PLA blocks as compared to those with amorphous PLA blocks. The drug release rate also depends significantly on the length of the PLA block. Sustained release of sulindac was observed up to 20 days, and for tetracaine up to 10 days. By comparison, release of these drugs without polymeric carriers occurs over 4-6h. This result, along with a proposed mechanism for drug release, suggests that polymer-drug interactions significantly impact release profiles, causing slow and sustained release of the drug.
More Related Videos
Related Concept Videos
Modified-Release Drug Delivery Systems: Rate-Programmed II
Modified-Release Drug Delivery Systems: Bioavailability
Modified-Release Drug Delivery Systems: Classification
Modified-Release Drug Delivery Systems: Rate-Programmed I
Oral Drug Delivery Systems: Delayed-Release Systems
Bioavailability Enhancement: Drug Solubility Enhancement

