河鲀毒素生物传感器的研究

Study on Biosensor for Detection of Tetrodotoxin in Fugu

基于河鲀毒素(TTX)对细胞膜Na+通道的阻断作用,建立一种检测TTX的简易组织生物传感器。组织生物传感器由pNa电极、青蛙膀胱膜、电位计等构成。在pNa电极顶端用两层醋酸纤维薄膜包裹,中间夹入青蛙膀胱膜,构成感受器。将电极插入pNa=4的NaCl溶液中,使电极输出信号趋于稳定。将TTX被测液注入感受器系统,测定感受器输出量的抑制值。每次测定只需5min。最低检出限为0.002MU/ml(3.56×10-3μg/ml)。用0.003%Na3N保存,可连续使用250h。以生物传感器和小鼠生物试验法比较,建立了工作曲线,便于在餐饮企业对原料鱼进行检测和应用。

A simple tissue biosensor for measuring Na^＋ channel blocks such as tetredotoxin（TrX） has been developed. The membrane of frog bladder has Na^＋ channels which control the passage of Na^＋. It is well known that TTX blocks Na^＋ channels. The tissue biosensor consists of a Na^＋ electrode integrated within a TTX solution. The tip of the electrode was covered with frog bladder membrane sandwiched between two sheets of cellulose acetate membrane, and the electrode was set in a TTX solution. The solution of pNa=4 NaCl was injected in the TTX solution and the output of the electrode allowed to stabilize. TTX was injected into the sensor system and measured from the inhibition ratio of the sensor peak output. One assay took approx 5min, The lower limit of detection was 0.0002μ g/ml. The continuous detention of TTX was feasible for 250h in the presence of 0.003% NAN3. A linear correlation was obtained between TTX activities in fugu muscles detected by methods of TTX sensor and mouse assay.