Lonati Silvia, Novembrino Cristina, Ippolito Silvia, Accinni Roberto, Galli Claudio, Troonen Hugo, Campolo Jonica, Della Noce Cinzia, Lunghi Giovanna, Catena Fabrizia Bamonti
Dipartimento Scienze Mediche, Università degli Studi, IRCCS Ospedale Maggiore Milano, Milan, Italy.
Clin Chem Lab Med. 2004 Feb;42(2):228-34. doi: 10.1515/CCLM.2004.041.
A fluorescence polarization immunoassay (FPIA) has been commercially released for routine large-scale testing of total homocysteine (tHcy) on the AxSYM analyzer. We evaluated the analytical performance of the AxSYM tHcy FPIA and compared it with the well established high-performance liquid chromatography (HPLC) and IMx tHcy FPIA methods. Homocysteine concentrations were measured by AxSYM and IMx tHcy FPIA and by a rapid isocratic HPLC method with fluorescence detection. Coefficient of variation (CV) of total imprecision for AxSYM tHcy was < or = 5%, mean dilution recovery 102%, analytical sensitivity 0.70 micromol/l and linearity was good up to 1:8 dilution. Spearman rank correlations, rho, were 0.83 (p < 0.0001) for AxSYM vs. HPLC, 0.97 (p < 0.0001) for AxSYM vs. IMx and 0.83 (p < 0.0001) for IMx vs. HPLC. Passing and Bablok regression Y-intercepts and slopes were: 2.944/0.937 (AxSYM vs. HPLC), -0.367/ 1.142 (AxSYM vs. IMx) and 2.632/0.805 (IMx vs. HPLC). Corresponding mean differences (AxSYM-Comparison Assay) recorded over a 5-50 micromol/l measured range were 1.80, -0.73 and 2.53 micromol/l. AxSYM tHcy FPIA's first rate precision, supported by the complete automation of the AxSYM analyzer, makes it fit for routine use and suitable for laboratories requiring homocysteine high-throughput testing capabilities.
一种荧光偏振免疫分析法（FPIA）已在AxSYM分析仪上商业化推出，用于总同型半胱氨酸（tHcy）的常规大规模检测。我们评估了AxSYM tHcy FPIA的分析性能，并将其与成熟的高效液相色谱法（HPLC）和IMx tHcy FPIA方法进行比较。通过AxSYM和IMx tHcy FPIA以及一种带有荧光检测的快速等度HPLC方法测量同型半胱氨酸浓度。AxSYM tHcy总不精密度的变异系数（CV）≤5%，平均稀释回收率为102%，分析灵敏度为0.70微摩尔/升，在高达1:8稀释时线性良好。AxSYM与HPLC的Spearman等级相关性rho为0.83（p<0.0001），AxSYM与IMx的相关性为0.97（p<0.0001），IMx与HPLC的相关性为0.83（p<0.0001）。Passing和Bablok回归的Y轴截距和斜率分别为：2.944/0.937（AxSYM与HPLC）、-0.367/1.142（AxSYM与IMx）和2.632/0.805（IMx与HPLC）。在5 - 50微摩尔/升的测量范围内记录的相应平均差异（AxSYM - 比较测定法）分别为1.80、-0.73和2.53微摩尔/升。AxSYM分析仪的完全自动化支持AxSYM tHcy FPIA的一级速率精密度，使其适合常规使用，适用于需要同型半胱氨酸高通量检测能力的实验室。
