Department of Chemistry, Faculty of Sciences and Technology, University of Coimbra, 3004-535 Coimbra, Portugal.
SensorLab, Department of Chemistry, University of Western Cape, 7535 Bellville, Cape Town, South Africa.
Food Chem. 2019 Jun 1;282:18-26. doi: 10.1016/j.foodchem.2018.12.104. Epub 2019 Jan 3.
The aim of the present work was to develop an amperometric biosensor for tyramine (Tyr) measurement in food and beverages. The biosensor architecture is based on tyrosinase (Tyr) immobilization on glassy carbon electrode modified by a nanocomposite consisting of gold nanoparticles (AuNP) synthesized by a green method and poly(8-anilino-1-naphthalene sulphonic acid) modified glassy carbon electrode. Under optimized experimental conditions for fixed potential amperometric detection, the biosensor exhibited a linear response to tyramine in the range 10-120 µM and the limit of detection was estimated to be 0.71 µM. The novel platform showed good selectivity, long-term stability, and reproducibility. The strong interaction between tyrosinase and the nanocomposite was revealed by the high value of the Michaelis-Menten constant (79.3 μM). The fabricated biosensor was successfully applied to the determination of Tyr in dairy products and fermented drinks with good recoveries, which makes it a promising biosensor for quantification of tyramine.
本工作旨在开发一种用于食品和饮料中天冬氨酸（Tyr）测量的电流型生物传感器。该生物传感器的结构基于辣根过氧化物酶（Tyr）固定在由通过绿色方法合成的金纳米粒子（AuNP）和修饰玻碳电极的聚（8-苯胺-1-萘磺酸）组成的纳米复合材料上。在固定电位电流型检测的优化实验条件下，该生物传感器对 10-120µM 范围内的天冬氨酸表现出线性响应，检测限估计为 0.71µM。新型平台表现出良好的选择性、长期稳定性和重现性。通过米氏常数（79.3µM）的高值揭示了辣根过氧化物酶和纳米复合材料之间的强相互作用。所制备的生物传感器成功地应用于乳制品和发酵饮料中天冬氨酸的测定，回收率良好，这使其成为一种有前途的天冬氨酸定量生物传感器。
