Protein adsorption of dialdehyde cellulose-crosslinked chitosan with high amino group contents

• Published in: Carbohydrate polymers 2017-05, Vol.163, p.34-42
• Main Authors: Kim, Ung-Jin, Lee, Yeong Ro, Kang, Tong Ho, Choi, Joon Weon, Kimura, Satoshi, Wada, Masahisa
• Format: Article
• Language: English
• Subjects: Adsorption; Cellulose - analogs & derivatives; Cellulose - chemistry; Chitosan; Chitosan - chemistry; Cross-Linking Reagents; Crosslinking; Cytotoxicity; Dialdehyde cellulose; Protein adsorption; Serum Albumin, Bovine - chemistry
• ISSN: 0144-8617; 1879-1344
• DOI: 10.1016/j.carbpol.2017.01.052

•Chitosan was crosslinked to dialdehyde cellulose (DAC) by Schiff base formation and subsequent reduction.•DAC-crosslinked chitosan showed complete resistance to solubilization in the acidic region in spite of a lower degree of crosslinking.•No cytotoxicity was observed on DAC-crosslinked chitosan during a 21-day long-term stability test.•DAC-crosslinked chitosan showed remarkably higher BSA adsorption capacity, resulting from increased amino group contents. Crosslinked chitosan was prepared by Schiff base formation between the aldehyde groups of dialdehyde cellulose (DAC) and the amino groups of chitosan and a subsequent reduction. DAC was obtained through periodate oxidation of cellulose and solubilization in hot water at 100°C for 1h. Three grades of DAC-crosslinked chitosan were prepared by adding various amounts DAC. The degrees of crosslinking as determined by amino group content were 3.8, 8.3, and 12.1%, respectively. DAC-crosslinked chitosan showed higher stability in the pH 2–9 range and no cytotoxicity was identified over the course of a 21-day long-term stability test. Also, DAC-crosslinked chitosan showed remarkably high bovine serum albumin (BSA) adsorption capacity at pH 5.5 as a result of the increased amino group content, due to the reaction between DAC and chitosan molecular chains occurring at multiple points even though DAC-crosslinked chitosan showed a lower degree of crosslinking.