乳酸脱氢酶的流动注射分析-电化学检测体系的研究

Studies on Flow Injection Analysis-Electrochemical Detection System for Analyzing L-Lactate Dehydrogenase

本文研究了L乳酸盐+NAD LDH丙酮酸+NADH+H^+的酶反应动力学曲线及NADH的电化学性质与流动伏安检测法,建立了乳酸脱氢酶(LDH)的单泵单液路流动注射分析-电化学检测体系。可测定LDH的活性和浓度。

The new system for analyzing lactate dehydrogenase(LDH) by means of flow injection analysis-electrochemical detection has been established. The system was a single flow-way with a single pump. The PTFE reaction tube was 15 cm long(0. 5 mmi. d. ). The LDH catalyzes the reaction between lactate and nicotinamideadenine dinucleotide(NAD). The nicotinamide adenine dinucleotide redused(NADH), which is product of above reaction, was determined by flow-cell amperometric detection. According to the kinetic curve obtained by spectrophotometry, the activity of LDH was determined.The carrier was composed of 0. 02 mol/L Na2HPO4, 0. 4 mol/L NaNO3 and 0. 06 mol/L lactic acid, the pH of the mixture was 9. 4. The flow rate was 200 μL/min. The sample solution contained 1. 015× 10-3 mol/L NAD, the sample volume injected was 10 μL. The working electrode was made of carbon paste and the potential was +0. 80 V(vs SCE).