Dolmaci Nezaket, Çete Servet, Arslan Fatma, Yaşar Ahmet
Gazi University, Ankara, Turkey.
Artif Cells Blood Substit Immobil Biotechnol. 2012 Aug;40(4):275-9. doi: 10.3109/10731199.2011.646410. Epub 2012 Jan 16.
A new amperometric biosensor was developed for determining hypoxanthine in fish meat. Xanthine oxidase with pyrrole and polyvinylsulphonate was immobilized on the surface of a platinum electrode by electropolymerization. The determination of xanthine-hypoxanthine was performed by means of oxidation of uric acid liberated during the enzyme reaction on the surface of the enzyme electrode at + 0.30V (SCE). The effects of pH, substrate concentration, and temperature on the response of the xanthine-hypoxanthine biosensor were investigated. The linear working range of the enzyme electrode was 1.0 × 10(-7) -1.0 × 10(-3) M of the hypoxanthine concentration, and the detection limit was 1.0 × 10(-7)M. The apparent K(m(app)) and I(max) of the immobilized xanthine oxidase were found to be 0.0154 mM and 1.203 μA/mM, respectively. The best pH and temperature value for xanthine oxidase were selected as 7.75 and 25°C, respectively. The sensor was used for the determination of hypoxhantine in fish meat. Results show that the fish degraded very rapidly after seven days and the hypoxanthine amount was found to increase over days of storage.
开发了一种用于测定鱼肉中次黄嘌呤的新型安培生物传感器。通过电聚合将含吡咯和聚乙烯磺酸盐的黄嘌呤氧化酶固定在铂电极表面。在酶电极表面于 +0.30V（饱和甘汞电极）下，通过氧化酶反应过程中释放的尿酸来测定黄嘌呤 - 次黄嘌呤。研究了pH值、底物浓度和温度对黄嘌呤 - 次黄嘌呤生物传感器响应的影响。酶电极的线性工作范围为次黄嘌呤浓度1.0×10⁻⁷ - 1.0×10⁻³ M，检测限为1.0×10⁻⁷ M。固定化黄嘌呤氧化酶的表观米氏常数K(m(app))和最大电流I(max)分别为0.0154 mM和1.203 μA/mM。黄嘌呤氧化酶的最佳pH值和温度值分别选定为7.75和25°C。该传感器用于测定鱼肉中的次黄嘌呤。结果表明，鱼肉在七天后迅速降解，且在储存期间次黄嘌呤含量增加。
