Guest Open Access Plus | Free Content | About | Sign in | New Users: Sign up | Mark List  

Current Medicinal Chemistry

Volume 18 Issue 36
ISSN: 0929-8673
eISSN: 1875-533X

 

   All Titles

  Poly(lactic acid)-poly(ethylene oxide) Block Copolymers: New Directions in Self-Assembly and Biomedical Applications
  pp.5676-5686 (11) Authors: E. M. Saffer, G. N. Tew, S. R. Bhatia
 
 
      Abstract

In this review, we focus on recent developments in biomaterials of poly(lactic acid)-poly(ethylene oxide)-poly(lactic acid) (PLA-PEO-PLA) triblock copolymers. This system has been widely explored for a number of applications in controlled and sustained release of drugs and in tissue engineering devices. New insights into self-assembly of these materials have resulted in new PLA-PEOPLA solutions and gels with novel structural, mechanical, and drug release properties. Recent innovations include hydrogels with nanoscale crystalline domains, solutions and gels based on PLA stereocomplexes, and nanoparticle-copolymer assemblies. We first briefly review synthetic approaches to these materials. We then describe characterization of the solution properties, formation of micelles, drug release characteristics, and investigation of the sol-gel transition. The properties of PLA-PEO-PLA hydrogels are then discussed, including the effect of crystalline domains on the gel microstructure and efforts to tune the elastic modulus and degredation properties of gels through the addition of chemical crosslinks. In the second half of the review, we discuss the wide variety of biomedical applications currently being pursued for PLA-PEO-PLA triblock copolymer systems. Polymer-nanoparticle complexes have been investigated to facilitate the formation of metal nanoclusters used as biosensors, as well as to enhance the elastic modulus of hydrogels. Thin polymer films have also been investigated for use as tissue engineering scaffolds and as drug-eluding coatings for stents and other medical implants. Finally, we discuss future directions for biomedical applications of this system, including new strategies for improving the specificity and cell affinity of PLA-based biomaterials.

 
  Keywords: Biosensors, drug delivery, drug eluting stents, hydrogel, poly(ethylene glycol), polymer micelle, poly(lactic acid), poly(lactide), PLA, lactide), biomaterials
  Affiliation: Department of Chemical Engineering, University of Massachusetts Amherst, Amherst, MA 01003, USA.
 
  Key: New Content Free Content Open Access Plus Subscribed Content

Bentham Science Publishers
www.benthamscience.com

 

  Copyright © 1994 - 2014   Bentham Science Publishers