Investigation of dialdehyde corn starch as crosslinking agent in collagen-based wound dressing materials

Abstract

Collagen is the most commonly used tissue-derived natural polymer. Collagen gels are widely used in wound dressing materials due to their good degradability, poor antigenicity, excellent biocompatibility and unique fibril forming properties. But, poor mechanical properties of physically formed collagen gels limit their usage in biomedical fields. However, collagen gels can be stabilized by using cross-linkers. In recent years, use of crosslinking agents obtained from biodegradable, low toxic, abundant, inexpensive and renewable sources in wound dressing materials for stabilization of collagen gels has become important. In the present study use of starch as a crosslinking agent in stabilization of collagen gels was investigated. For this purpose native starch was modified via oxidation of corn starch by NaIO4 in order to obtain dialdehyde starch. Then, the degree of substitution and swelling index of oxidized starches were determined and the starch samples were characterized by Fourier transforms infrared (FT-IR) spectroscopy and Scanning Electron Microscopy (SEM). Collagen gels were crosslinked with dialdehyde starch samples for preparing wound dressing materials. The collagen gel composites were lyophilized and sponge forms were obtained. They were characterized by water uptake capacity and enzymatic degradation. The results revealed that, dialdehyde corn starch can be used successively in collagen-based wound dressing materials as crosslinking agent.