Xue Q, Yeung E S
Ames Laboratory-USDOE and Department of Chemistry, Iowa State University, Ames 50011.
Anal Chem. 1994 Apr 1;66(7):1175-8. doi: 10.1021/ac00079a036.
Trace amounts of enzymes within single human erythrocytes can be quantified by a combination of on-column reaction and capillary electrophoresis. A detection limit of 1.3 x 10(-21) mol of LDH was achieved with laser-induced fluorescence by monitoring the product of the enzyme-catalyzed reaction between lactate and NAD+. Single erythrocyte analysis clearly isolates the major forms of LDH. The variation of total LDH activity in a population of cells from a single individual is large, but the relative activities of the isoenzymes LDH-1 and LDH-2 are fairly constant. This can be explained by the distribution of cell age in the population. A lower enzyme activity is indicative of senescence. The efficient separation of different LDH forms and the high detection sensitivity opens up the possibility of multiple-enzyme assays with a single mammalian cell.
通过柱上反应和毛细管电泳相结合的方法，可以对单个人类红细胞内的痕量酶进行定量分析。通过监测乳酸与NAD +之间酶催化反应的产物，利用激光诱导荧光实现了对乳酸脱氢酶（LDH）1.3×10（-21）摩尔的检测限。单个红细胞分析清楚地分离出LDH的主要形式。来自单个个体的细胞群体中总LDH活性的变化很大，但同工酶LDH-1和LDH-2的相对活性相当恒定。这可以通过群体中细胞年龄的分布来解释。较低的酶活性表明细胞衰老。不同LDH形式的高效分离和高检测灵敏度为单个哺乳动物细胞的多酶检测开辟了可能性。
