Chiou W L, Gadalla M A, Peng G W
J Pharm Sci. 1978 Feb;67(2):182-7. doi: 10.1002/jps.2600670215.
Previously published methods for endogenous creatinine levels in plasma, serum, or urine lack specificity or are subject to interferences from endogenous or exogenous substances. The developed simple, rapid, and specific high-pressure liquid chromatographic method includes the novel deproteinization and extraction of 1 volume of plasma or serum with 2.5 volumes of acetonitrile and also of 1 volume of urine with 40 volumes of a 20% water-80% acetonitrile solution. An aliquot of the supernate is then injected directly into the chromatograph. A cation-exchange column and acidified (0.02% of 85% phosphoric acid) 0.1 M ammonium phosphate solution as the mobile phase, with a flow rate of 2 ml/min, were used. Creatinine, with a retention time of 3.8 min, was monitored via its UV absorption at 215 nm. Both peak heigh and integrated area methods of quantitation yielded the same results. Several methods were employed to show that the "suspected" creatinine peak from plasma samples was due entirely to the "true" creatinine. No interference was found in samples obtained from normal and renal patients. The day-to-day variation in the detector response was small. Each assay requires only about 5 min for completion. Ten microliters of plasma or serum or 1 microliter of urine is sufficient for analysis.
先前已发表的用于测定血浆、血清或尿液中内源性肌酐水平的方法缺乏特异性，或易受到内源性或外源性物质的干扰。所开发的简单、快速且特异的高压液相色谱法包括用2.5倍体积的乙腈对1体积的血浆或血清进行新型的去蛋白和提取，以及用40倍体积的20%水-80%乙腈溶液对1体积的尿液进行同样操作。然后将上清液的一份子直接注入色谱仪。使用阳离子交换柱和酸化（85%磷酸的0.02%）的0.1 M磷酸铵溶液作为流动相，流速为2 ml/min。肌酐的保留时间为3.8分钟，通过其在215 nm处的紫外吸收进行监测。峰高和积分面积定量方法均得出相同结果。采用了几种方法来表明血浆样品中“疑似”的肌酐峰完全归因于“真实”的肌酐。在正常人和肾病患者的样品中均未发现干扰。检测器响应的日常变化很小。每次测定仅需约5分钟即可完成。10微升血浆或血清或1微升尿液就足以进行分析。
