초록 |
The most plentiful component of exoskeletons in invertebrates is chitin, which is the second most abundant naturally occurring biopolymer by living organisms. And chitosan, one of the most important derivative of chitin, is an appealing biopolymer for the replacement of synthetic plastics and applicable to various biomedical fields. Here, we measured the interaction forces of chitosan (adhesion and cohesion) in aqueous solutions by exploring the effects of molecular weight (135 k & 5 k), contact time and degree of acetylation (DA) using a surface forces apparatus. The DA, which determines the chitin and chitosan, was precisely regulated by acetic anhydrides inducing the reacetylation of chitosan. The measured adhesion forces decreased as an increase of DA regardless of the molecular weight, while only the cohesion of 5 k chitosan increased as DA. These findings will provide a new insight into the future applications of chitin and chitosan based materials. |