Abstract In the present study, a protein-based halochromic nanosensor was designed to assess the quality of rainbow trout fillets. Zein nanofibers containing alizarin as the indicator dye were electrospun. The sensors were characterised using SEM, FT-IR, DSC, XRD, dye leaching, response time experiments and colorimetric analysis. TVB-N, TVC and pH of fish fillets were also measured over 12 days of storage at 4 °C. FT-IR results showed that the alizarin was incorporated in the zein matrix by intermolecular hydrogen bonding. DSC graphs of zein based samples showed that the temperature of dehydration, glass transition and protein unfolding in the halochromic nanofibers were lower than in powdered zein. The amorphous structure of the zein samples was confirmed by XRD analysis. No color changes were occurred in the first 4 days of storage, but later, a light purple color could be observed in the sensor by the naked eye. The color of sensor became magenta by the 10th and 12th day of cold storage indicating spoilage. This fabricated halochromic nanosensor can monitor fish freshness in real time through color changes. The colorimetric results correlated well with microbial and chemical changes in the fish.

中文翻译：

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用于监测鳟鱼新鲜度的基于蛋白质的卤致变色电纺纳米传感器

摘要 在本研究中，设计了一种基于蛋白质的卤色纳米传感器来评估虹鳟鱼片的质量。含有茜素作为指示染料的玉米醇溶蛋白纳米纤维是电纺的。使用 SEM、FT-IR、DSC、XRD、染料浸出、响应时间实验和比色分析对传感器进行表征。还测量了鱼片在 4°C 下储存 12 天后的 TVB-N、TVC 和 pH 值。FT-IR 结果表明茜素通过分子间氢键结合到玉米醇溶蛋白基质中。基于玉米醇溶蛋白的样品的 DSC 图显示，在卤致变色纳米纤维中，脱水、玻璃化转变和蛋白质解折叠的温度低于粉状玉米醇溶蛋白。通过XRD分析证实了玉米蛋白样品的无定形结构。储存的前 4 天没有发生颜色变化，但后来，肉眼可以在传感器中观察到浅紫色。到冷藏的第 10 天和第 12 天，传感器的颜色变为洋红色，表明已损坏。这种制造的卤色纳米传感器可以通过颜色变化实时监测鱼的新鲜度。比色结果与鱼的微生物和化学变化密切相关。