Chiknas S G
Clin Chem. 1979 Jul;25(7):1259-62.
I describe modification of the spectrophotometric assay described by Cushman and Cheung [biochem. Pharmacol. 20, 1637 (1971)] for serum angiotensin-converting enzyme, with use of "high-pressure" liquid chromatography to measure the hippuric acid end product. After reaction of 10 microL of untreated serum with the angiotensin-converting enzyme substrate analog hippuryl-L-histidyl-L-leucine, the hippuric acid produced is extracted into ethyl acetate and quantitated, relative to an added internal standard, by liquid chromatography. Total chromatographic running time is 3 min per sample, with a within-run CV of 4.3% and a day-to-day CV of 6.6%, for aliquots of plasma supplemented with 1 mmol of hippuric acid per liter. The measurements are linear for hippuric acid in amounts up to 20 nmol per assay. The presence of large quantities of lipid in the serum did not affect the accuracy of the determination.
我描述了对库什曼和张[《生物化学与药理学》20, 1637 (1971)]所描述的用于测定血清血管紧张素转换酶的分光光度法的改进，采用“高压”液相色谱法来测量马尿酸终产物。将10微升未处理的血清与血管紧张素转换酶底物类似物马尿酰-L-组氨酰-L-亮氨酸反应后，产生的马尿酸被萃取到乙酸乙酯中，并相对于添加的内标物通过液相色谱法定量。每个样品的总色谱运行时间为3分钟，对于每升添加1毫摩尔马尿酸的血浆等分试样，批内变异系数为4.3%，日间变异系数为6.6%。每次测定中马尿酸含量高达20纳摩尔时，测量呈线性。血清中大量脂质的存在不影响测定的准确性。
