两种磁分离酶联免疫法检测血清甲胎蛋白

Detection of alpha fetoprotein in serum with two kinds of magnetic enzyme immunoassay

目的改进磁分离酶联免疫法(MEIA)。方法采取预加微量标本、将磁铁置于微孔条侧壁和扣除上清液A值法,改良MEIA并建立了"差异磁分离酶联免疫法"(differential magnetic enzyme immunoassay,DMEIA)。求DMEIA法的线性范围、回归方程、变异系数(CV),比较了MEIA和DMEIA配对检测100份血清AFP结果差异。结果 DMEIA法检测AFP的回归方程Y=3.94X+16.45,r=0.992,线性范围5～500ng/mL,批内CV=7.7%,批间CV=8.5%;DMEIA法和MEIA法测定血清AFP值差异无统计学意义(t检验,P>0.05),直线回归方程Y=3.418X+70,r=0.981,两法相关良好;检测原倍高浓度AFP时DMEIA法未出现(MEIA法出现)hook效应。结论 DMEIA法可克服hook效应,可用普通微孔板和酶标仪比色,可省去洗涤步骤,检测AFP结果(<500ng/mL时)与MEIA法无明显差异。

Objective To improve magnetic enzyme immunoassay（MEIA）. Methods By pre-adding micro-quantity of sample,putting the magnetic bar beside the micro wells, deducting the A figures of the partial supernatant, the ＂differential magnetic enzyme immunoassay＂ （DMEIA） was established. One hundred serum samples were tested for quantitative analysis of AFP by DMEIA and MEIA. Results For detection of AFP by DMEIA,the regression equation is Y= 3.94X＋ 16.45, r= 0. 992, the linear scope is 5- 500 ng/mL, the inner and intra coefficients of variation（CV）were 7.7 % and 8.5 % respectively. The difference between the results of compared detections by DMEIA and MEIA showed no statistic significance（t-test, P〉0.05）, the regression equation for the two methods is Y=3. 418X＋70,r=0. 981. On detecting the high eoneentration（21460-501690ng/mL）of AFP,DMEIA did not show（MEIA showed） the hook effect. Conclusion The DMEIA could save the rinse,overcome the hook effect,be suitable for general EIA instruments and issued the AFP results not different significantly with those of MEIA（〈500 ng/mL）.