酶法测定乳酸

利用乳酸在氧化型烟酰胺腺嘌呤二核苷酸（NAD）存在的条件下，由乳酸脱氢酶（L-LDH）催化生成丙酮酸和还原型烟酰胺腺嘌呤二核苷酸（NADH）。通过测定NADH吸光度的变化率可得出乳酸的酶促反应速度，并制得标准曲线。样品中的乳酸可由标准曲线求得。讨论了试剂用量、pH、温度和共存离子对测定的影响。

Enzymatic determination of L-lactic acid

An enzymatic method was applied to determine L-lactic acid based on the reaction of L-lactic acid and nicotinamide adenine dinucleotide oxidized form(NAD) catalyzed by L-lactate dehydrogenase(L-LDH). The rate of absorbance change of nicotinamide adenine dinucleotide reduced form (NADH) was determined for calculating the speed of the enzymatic reaction and the calibration curve of L-lactic acid was drawn. The L-lactic acid in samples was determined by the calibration curve.The effects of the amount of reagents, pH value, temperature of reaction and coexisting ions in the solution were discussed. This method has advantages of rapidity and simplicity.