>>
>>
关键字：Shellfish;Acetylation - Ammonium persulfate - Calcite - Calcium carbonate - Carboxylation - Chitin - Disintegration - Hydrogels - Molluscs - Nanofibers
摘要：TEMPO-mediated oxidation has been successfully used to prepare carboxylated chitin nanofibers (ChNFs) with purified chitins originating from the outer shells of crab and shrimp (α-form) or tubeworm (β-form). However, the method for obtaining carboxylated ChNFs with squid pen chitin (hydrated β-form) has not been developed yet. It might be due to the existence of the small amount of partial deacetylation (DD ≈ 9%) in the squid pen β-chitins. Herein, ultrafine (2–4 nm in width and several micrometers in length) and carboxylated β-ChNFs were fabricated directly from the squid pen with simultaneously removing of protein, CaCO3 and other non-chitin components by one-step oxidation procedure using ammonium persulfate (APS) and followed ultrasonic disintegration under acid conditions. When 45 wt% APS was used to react with squid pen, the carboxylate content of ChNFs reaches 0.802 mmol/g. Therefore, the β-ChNFs with anionically charged groups (COO<sup>−</sup>) can be dispersed stably in aqueous solution under basic conditions. Meanwhile, thus-obtained β-ChNFs aqueous solution even with very low concentration (0.8%) can be transformed to transparent, robust and moldable hydrogels by gas coagulation of acetic acid.<br/> © 2019 Elsevier Ltd
卷号：211
是否译文：否
