Modified PHBV scaffolds by in situ UV polymerization: structural characteristic, mechanical properties and bone mesenchymal stem cell compatibility.

An ideal scaffold provides an interface for cell adhesion and maintains enough biomechanical support during tissue regeneration. Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) scaffolds with pore sizes ranging from 100 to 500 microm and porosity approximately 90% were prepared by the particulate-leaching method, and then modified by the introduction of polyacrylamide (PAM) on the inner surface of scaffolds using in situ UV polymerization, with the aim of enhancing the biological and mechanical properties of the PHBV scaffolds. The modified PHBV scaffolds had interconnected pores with porosity of 75.4-78.6% and pore sizes at peak volume from 20 to 50 microm. The compressive load and modulus were up to 62.45 N and 1.06 MPa, respectively. The water swelling percentage (WSP) of the modified PHBV scaffolds increased notably compared with that of the PHBV scaffolds, with the maximum WSP at 537%. Sheep bone mesenchymal stem cells (BMSC) were cultured on the PHBV and modified PHBV. The hydrophilic PAM chains did not influence BMSC viability or proliferation index, but the initial cell adhesion at 1h of culture was enhanced significantly. Framing PHBV scaffold along with gel-like PAM chains inside is a novel model of inner surface modification for PHBV scaffolds, which shows potential in tissue engineering applications.

[1]  A. Kocabas,et al.  Chemical and topographical modification of PHBV surface to promote osteoblast alignment and confinement. , 2008, Journal of biomedical materials research. Part A.

[2]  G. Whitesides,et al.  Promotion of opsonization by antibodies and phagocytosis of Gram-positive bacteria by a bifunctional polyacrylamide. , 2006, Biomaterials.

[3]  Gang Wu,et al.  Surface engineering of PHBV by covalent collagen immobilization to improve cell compatibility. , 2009, Journal of biomedical materials research. Part A.

[4]  V. Langlois,et al.  Modification of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) film by chemical graft copolymerization. , 2007, Biomacromolecules.

[5]  J. Vacanti,et al.  Tissue engineering : Frontiers in biotechnology , 1993 .

[6]  B. Rånby.  Surface modification and lamination of polymers by photografting , 1999 .

[7]  Michael J. Tarlov,et al.  UV Graft Polymerization of Polyacrylamide Hydrogel Plugs in Microfluidic Channels , 2003 .

[8]  C. Werner,et al.  Surface modification of poly(hydroxybutyrate) films to control cell-matrix adhesion. , 2007, Biomaterials.

[9]  Y. Tokiwa,et al.  Degradation of microbial polyesters. , 2004, Biotechnology letters.

[10]  Guoqiang Chen,et al.  The application of polyhydroxyalkanoates as tissue engineering materials. , 2005, Biomaterials.

[11]  W. Tsai,et al.  Spatial control of cellular adhesion using photo-crosslinked micropatterned polyelectrolyte multilayer films. , 2009, Biomaterials.

[12]  Gang Wu,et al.  Photografting polymerization of polyacrylamide on PHBV films (I) , 2007 .

[13]  M S Chapekar,et al.  Tissue engineering: challenges and opportunities. , 2000, Journal of biomedical materials research.

[14]  Kwideok Park,et al.  Effect of RGD-immobilized dual-pore poly(L-lactic acid) scaffolds on chondrocyte proliferation and extracellular matrix production. , 2008, Artificial organs.

[15]  Jong-Chul Park,et al.  Enhanced chondrogenic responses of articular chondrocytes onto porous silk fibroin scaffolds treated with microwave-induced argon plasma , 2008 .

[16]  F. Korkusuz,et al.  Poly(3-hydroxybutyric acid-co-3-hydroxyvaleric acid) based tissue engineering matrices , 2003, Journal of materials science. Materials in medicine.

[17]  Zhifei Chen,et al.  Block poly(ester-urethane)s based on poly(3-hydroxybutyrate-co-4-hydroxybutyrate) and poly(3-hydroxyhexanoate-co-3-hydroxyoctanoate). , 2009, Biomaterials.

[18]  T. Ushida,et al.  Hybrid Biomaterials for Tissue Engineering: A Preparative Method for PLA or PLGA–Collagen Hybrid Sponges , 2000 .

[19]  Y. Tokiwa,et al.  Review Degradation of microbial polyesters , 2004, Biotechnology Letters.

[20]  Linbo Wu,et al.  A comparative study of porous scaffolds with cubic and spherical macropores , 2005 .

[21]  A. R. Santos,et al.  Increased response of Vero cells to PHBV matrices treated by plasma , 2008, Journal of materials science. Materials in medicine.

[22]  D. Mooney,et al.  Hydrogels for tissue engineering. , 2001, Chemical reviews.

[23]  J. Vacanti,et al.  Tissue engineering. , 1993, Science.

[24]  J. Guenet,et al.  Anomalous behaviour of comb-like dextran–polyacrylamide copolymers in mixed solvents , 2009 .

[25]  R. Marchessault,et al.  Bacterial polyesters: biosynthesis, biodegradable plastics and biotechnology. , 2005, Biomacromolecules.

[26]  T. Groth,et al.  Studies on cell-biomaterial interaction: role of tyrosine phosphorylation during fibroblast spreading on surfaces varying in wettability. , 1996, Biomaterials.

[27]  D. Hutmacher,et al.  Scaffolds in tissue engineering bone and cartilage. , 2000, Biomaterials.

[28]  Yen Wah Tong,et al.  Proteins combination on PHBV microsphere scaffold to regulate Hep3B cells activity and functionality: a model of liver tissue engineering system. , 2007, Journal of biomedical materials research. Part A.

[29]  Robert E. Nordon,et al.  Mesenchymal stem cells in tissue engineering , 2008 .