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Publications (2)9.91 Total impact

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    ABSTRACT: Peptides containing the sequence of arginine-glycine-aspartate (RGD), a famous adhesion moiety, can specifically conjugate integrins in cell membranes, and are usually applied to enhance cell adhesion after linking to solid substrates in tissue engineering or to nanoparticles in targeting delivery. This paper reveals, however, that free RGD peptides can assist in preventing tissue adhesion by blocking focal adhesion between cells and surfaces of barrier devices. In order to avoid a rapid peptide loss after straightforward injection of a peptide solution, we employed a thermosensitive injectable hydrogel composed of a biodegradable block copolymer poly(ε-caprolactone-co-lactide)-poly(ethylene glycol)-poly(ε-caprolactone-co-lactide) (PCLA-PEG-PCLA) to encapsulate peptides cyclo(-RGDfK-). A sustainable release for one week was achieved in vitro. The rabbit model of sidewall defect and bowel abrasion was selected to examine the in vivo anti-adhesion efficacy. It reveals a significant reduction of postoperative peritoneal adhesion in the group of RGD-loaded PCLA-PEG-PCLA hydrogels. We interpret this excellent efficacy by the combination of two effects: first, our hydrogel affords a physical barrier to prevent adhesion between injured abdominal wall and cecum; second, the RGD molecules as integrin blockers released from the hydrogel assist the anti-adhesion.
    Journal of Biomedical Materials Research Part B Applied Biomaterials 06/2012; 100(6):1599-609. · 2.31 Impact Factor
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    ABSTRACT: Biodegradable polymers can serve as barriers to prevent the post-operative intestinal adhesion. Herein, we synthesized a biodegradable triblock copolymer poly(ɛ-caprolactone-co-lactide)-b-poly(ethylene glycol)-b-poly(ɛ-caprolactone-co-lactide) (PCLA-PEG-PCLA). The concentrated polymeric aqueous solution was injectable, and a hydrogel could be rapidly formed due to percolation of a self-assembled micelle network at the body temperature without requirement of any chemical reactions. This physical hydrogel retained its integrity in vivo for a bit more than 6 weeks and was eventually degraded due to hydrolysis. The synthesized polymer exhibited little cytotoxicity and hemolysis; the acute inflammatory response after implanting the hydrogel was acceptable, and the degradation products were less acidic than those of other polyester-containing materials. A rabbit model of sidewall defect-bowel abrasion was employed, and a significant reduction of post-operative peritoneal adhesion has been found in the group of in situ formed PCLA-PEG-PCLA hydrogels.
    Biomaterials 07/2011; 32(21):4725-36. · 7.60 Impact Factor