循环酶法测定血浆同型半胱氨酸

Determination of plasma homocysteine by enzymatic cycling assay

目的 建立简便的循环酶法，直接检测血浆同型半胱氨酸（Hcy）。方法 在Hitachi 7170S全自动生化分析仪上，以循环酶法测定血浆Hey，采用两点速率法，主波长340nm，副波长405nm，温度37℃，两点线性校准。结果 本法线性范围1．5—50μmol／L；日内不精密度为2．2％-3．0％，日间不精密度为4．0％-5．9％；回收率为94．6％-102．5％。循环酶法（Y）和商品试剂盒（X）比较：Y=1．018X-0．895，决定系数（r^2）=0．945。结论 循环酶法简便、灵敏，试剂稳定，适用于血浆Hcy的常规和自动化分析。

Objective To establish a simple enzymatic cycling assay for determining homocysteine （Hcy） in plasma. Methods The plasma Hcy was detected by enzymatic cycling method on Hitachi 7170S automatic analyzer. The determation parameter： 2-point rate assay, 2-point linear calibration, the temperature was 37 ℃, the main wavelength was 340 nm and the secondary wavelength was 405 nm. Results The linearity of this method was 1.50-50 μmol/L. The within-run coefficien of variation（CV） was 2.2% -3.0% , the between-run CV was 4.0% -5.9%. The recovery rate was 94.6%-102.5%. Correlation between results obtained by this method（Y） and commercial reagent assay（X） was Y = 1. 018X-0.895 ,decisive coefficien（ r^2） =0.945. Conclusions The method is simple, sensitive and stable for routine and automatic measurement of Hey in plasma.