ИСТИНА

Neuropathy target esterase (NTE) was shown to be a biochemical marker for screening of organophosphates (OPs) with respect to their ability to result in organophosphate-induced delayed neuropathy (OPIDN). The inhibition/aging of neuronal NTE within hours of exposure to OP predicts potential for the development of OPIDN after a delay of 1-3 weeks. Development of biosensors for express NTE analysis used in monitoring systems for individuals exposed to neuropathic OP is the aim of this work. The principle of biosensors for the analysis of NTE and its inhibitors is based on the combination of NTE enzymatic hydrolysis of phenyl valerate with a detection of phenol by tyrosinase electrodes. The Clark-type oxygen electrode modified by tyrosinase immobilized in polyvinylalcohol (1) and tyrosinase carbon-paste electrode (2) were used for a construction of the biosensors. Both biosensors were found to be suitable for measurements of NTE activity of in whole human blood when the application of a conventional spectrophotometric detection is limited. The values of inhibitor specificity of NTE in blood for mipafox and diisopropylfluorophosphate were close to those for neuronal NTE. The NTE-like activity in blood was determined to be 0.19 +/- 0.02 mmoles/min per mg of protein.