Poster Session

Start Date

20-5-2016 12:30 PM

Document Type

Poster Abstract

Description

Biodegradable polymers have been widely utilized as drug delivery vehicles and tissue engineering scaffolds. We previously designed amphiphilic triblock copolymer poly(lactic acid)-b-poly(ethylene glycol)-b-poly(lactic acid) (PELA) and its hydroxyapatite (HA) composites for bone tissue engineering applications. The hydrophilic electrospun PELA-HA composite exhibited aqueous stability and elastic handling characteristics, and was able to template the proliferation and osteogenesis of bone marrow stromal cells (BMSCs) in vitro and in vivo when spiral-wrapped into cylinders and press-fit into critical size femoral segmental defects in rats. However, the slow degradation of PELA has prevented timely disappearance of the scaffold and impeded more effective restoration of biomechanical integrity of the defect. To accelerate degradation, in this work we designed poly(lactic/glycolic acid)-b-poly(ethylene glycol)-b-poly(lactic/glycolic acid) (PELGA) with varying ratios of glycolide and lactide and confirmed their more accelerated degradations as compared to PELA. Processing conditions (e.g. solvent-casting vs. electrospinning, with or without hydration) significantly impacted the structural characteristics of PELGA and their HA composites. The PEG crystallization in PELGA was not as strong as in PEG homopolymers, giving rise to a lower Tm. HA could be well dispersed in PELGA and electrospun to give a uniform composite where the crystallization of PEG was promoted by water resulting in enhanced mechanical strength upon hydration. These HA-contained electrospun meshes exhibited excellent cytocompatibility and efficacy in templating osteogenesis of rat BMSCs in vitro.

Keywords

Biodegradable polymers, drug delivery, tissue engineering application

Creative Commons License

Creative Commons Attribution-Noncommercial-Share Alike 3.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 License.

Share

COinS
 
May 20th, 12:30 PM

Optimization of the Design of an Amphiphilic Biodegradable Polymer for Tissue-engineering Application

Biodegradable polymers have been widely utilized as drug delivery vehicles and tissue engineering scaffolds. We previously designed amphiphilic triblock copolymer poly(lactic acid)-b-poly(ethylene glycol)-b-poly(lactic acid) (PELA) and its hydroxyapatite (HA) composites for bone tissue engineering applications. The hydrophilic electrospun PELA-HA composite exhibited aqueous stability and elastic handling characteristics, and was able to template the proliferation and osteogenesis of bone marrow stromal cells (BMSCs) in vitro and in vivo when spiral-wrapped into cylinders and press-fit into critical size femoral segmental defects in rats. However, the slow degradation of PELA has prevented timely disappearance of the scaffold and impeded more effective restoration of biomechanical integrity of the defect. To accelerate degradation, in this work we designed poly(lactic/glycolic acid)-b-poly(ethylene glycol)-b-poly(lactic/glycolic acid) (PELGA) with varying ratios of glycolide and lactide and confirmed their more accelerated degradations as compared to PELA. Processing conditions (e.g. solvent-casting vs. electrospinning, with or without hydration) significantly impacted the structural characteristics of PELGA and their HA composites. The PEG crystallization in PELGA was not as strong as in PEG homopolymers, giving rise to a lower Tm. HA could be well dispersed in PELGA and electrospun to give a uniform composite where the crystallization of PEG was promoted by water resulting in enhanced mechanical strength upon hydration. These HA-contained electrospun meshes exhibited excellent cytocompatibility and efficacy in templating osteogenesis of rat BMSCs in vitro.

 

To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.