New method for coupling collagen on biodegradable polyurethane for biomedical application

Abstract

Abstract A two‐step method was used in this article to synthesize a novel biodegradable polyurethane (PU) composed by L ‐lysine ethyl ester diisocyanate (LDI) hard segment, poly(ε‐caprolactone) diols (PCL‐diol) soft segment and 1,4:3,6‐dianhydro‐ D ‐sorbitol (isosorbide) chain extender. FTIR, 1 H‐NMR results revealed the products had typical PU structures. GPC result showed that the number average molecular weight of the PU was 36,800 with the heterodisperse index of 2.18. DSC result displayed the PU melting temperature was 42°C. Surface aminolyzing of the PU membrane was performed by reacting it with 1,3‐propanediamine under alkaline condition. Then, type I collagen was grafted on the PU surface by EDC/NHS coupling method. Rhodamine B isothiocyanate (RBITC) fluorescence spectrum presented that both amino group (NH 2 ) and type I collagen were successfully introduced on the PU surface. Furthermore, ninhydrin analysis showed that the maximum surface density of amino groups was 11.4 × 10 −7 mol/cm 2 after aminolyzing in 12% 1,3‐propanediamine aqueous solution for 1 h. Cell viability experiments indicated both PU‐NH 2 and PU‐Col had low cytotoxicity and supported the ATDC5 cell's proliferation on them. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012