Water-uptake properties of a fish protein-based superabsorbent hydrogel chemically modified with ethanol

Abstract Hydrophilic polymers can form hydrogels, which are able to absorb and retain as much water as one hundred times their weight. Polymers based on natural products have been drawing attention since they are biocompatible, biodegradable and nontoxic. The aims of this study were to produce and to characterize a biopolymer with superabsorbent properties from fish protein isolates. Hydrogels were produced from protein isolates from Whitemouth croaker processing wastes chemically modified. The extension of change in lysine residues, kinetics in water-uptake capacity, pH effect, ionic strength over the absorption of water by hydrogels and the behavior of the biopolymer when subject to successive hydration and dehydrations were investigated. Results showed that acid modified protein without ethanol treatment reached a maximum absorption of 103.25 gwater/gdry gel, while the same sample modified with ethanol reached 216.05 gwater/gdry gel.

摘要 亲水聚合物（hydrophilic polymers）可形成水凝胶（hydrogels），其能够吸收并留存高达自身重量百倍的水分。基于天然产物的聚合物因兼具生物相容性、可生物降解性与无毒性而受到广泛关注。本研究旨在从鱼类加工废弃物中提取鱼蛋白分离物（fish protein isolates），以此为原料制备并表征具有高吸水性能的生物聚合物。实验以白嘴石首鱼（Whitemouth croaker）加工废弃物中的分离蛋白为原料，经化学改性制备水凝胶。本研究考察了赖氨酸残基（lysine residues）的改性程度、水凝胶的吸水动力学、pH值与离子强度对其吸水量的影响，以及该生物聚合物在反复水合-脱水循环中的性能表现。结果显示，未经乙醇处理的酸改性蛋白凝胶最大吸水量可达103.25 g水/克干凝胶，而经乙醇处理的改性样品最大吸水量可达216.05 g水/克干凝胶。