ABSTRACT
OBJECTIVE：To investigate the consistency and difference of f luorescence immunochromatographic and liquid chromatography-tandem mass spectrometry （LC-MS/MS）and enzyme multiplied immunoassay technique （EMIT）in the blood concentration monitoring of mycophenolic acid. METHODS ：Fluorescence immunochromatography ，LC-MS/MS and EMIT were used to detect the blood concentration of mycophenolic acid in 61 blood samples of children treated with mycophenolate mofetil ester orally at different time points. Kolmogorov-Smirnov method ，Wilcoxon pairing test ，Passing-Bablok regression ，Cusum method，Spearman correlation analysis ，Bland-Altman scatter diagram were adopted for statistical analysis. RESULTS ：Blood concentrations of mycophenolic acid ，which were determined by fluorescence immunochromatography ，LC-MS/MS and EMIT ， showed non-normal distribution. Passing-Bablok regression analysis showed that regression equation of fluorescence immunochromatography and LC-MS/MS ，fluorescence immunochromatographic method and EMIT were CFI=0.928 3CLC-MS/MS+0.961 7 and CFI＝0.880 7CEMIT－0.488 2（FI means fluorescence immunochromatographic ）. Spearman correlation analysis showed that the correlation coefficients between fluorescence immunochromatography and LC-MS/MS ，fluorescence immunochromatography and EMIT were 0.968 and 0.929， respectively （P＜0.000 1）. Bland Altman scatter plot analysis showed that 3.28％ of the 358341451@qq.com difference between fluorescence immunochromatography and LC-MS/MS was outside the consistency limit （±1.96SD）， and 1.64％ of the difference between fluorescence immuno- chromatography and EMIT was outside the consistency limit （± 1.96SD）. Wilcoxon pairing test showed that the results of fluorescence immunochromatography were higher than those of LC-MS/MS （Z＝3.76，P＝0.000 2）and lower than those of EMIT （Z＝－5.96，P＜0.000 1）. CONCLUSIONS ：Fluorescence immunochromatography shows good consistency and correlation with LC-MS/MS and EMIT ；the blood concentrations of mycophenolic acid detected by fluorescence immunochromatography were higher than those by LC-MS/MS and lower than those by EMIT . It can be used for bedside rapid detection. When using the test results of different methods for clinical medication ，the differences of test methods need to be considered.
ABSTRACT
Objective:To establish a rapid and quantitative method for the determination of immunoglobulin G4 (IgG4) by fluorescence immunochromatography and to analyze its clinical application value.Methods:Fluorescence immunoassay for quantitative detection of IgG4 was obtained by means of preparation of kits in a competitive reaction mode and combining immunoassay with fluorescence quantitative assay. The linearity, precision, accuracy, anti-interference ability and stability of the method were evaluated, and compared with immune-scattering turbidimetry, receiver operating characteristic curve (ROC) was plotted, area under the curve (AUC) was calculated, and the critical value for the diagnosis of pancreatitis related diseases was determined, and sensitivity and specificity were calculated.Results:The linear range of fluorescence immunoassay for IgG4 was 0.2-10.0 g/L. The accuracy coefficient of variation was less than 15%, and the accuracy deviation was within ±15%. Bilirubin (2.5 g/L), triglyceride (10 g/L) and hemoglobin (10 g/L) had no significant effect on the quantitative determination. Within 14 months, 1.20 g/L and 2.65 g/L reference samples were detected with concentration deviations within ±15%. The kit validity period was >12 months. Serum samples of 200 healthy people were detected by fluorescence immunochromatography, and the normal reference value of IgG4 was <2.03 g/L. fluorescence immunochromatography and Immunoturbidimetry were used to detect IgG4 concentrations in 383 clinical serum samples. The results showed that the two methods were consistent ( P>0.05). Using 2.01g/L IgG4 as the critical value, the sensitivity and specificity of fluorescence immunochromatography were 96.3% and 95.5% by ROC curve analysis, respectively. Conclusions:Fluorescence immunochromatography was a simple, rapid and accurate method for the quantitative detection of IgG4, and had high sensitivity and specificity for the diagnosis of pancreatitis related diseases. It was suitable for quantitative detection of bulk samples in outpatient and emergency departments.
ABSTRACT
To establish a time-resolved fluorescence immunochromatographic assay for quantitative determination of carbohydrate antigen 19-9 (CA19-9) in serum, we prepared CA19-9 test strips by integrating double-antibody sandwich method and fluorescence immunochromatography technique. Carboxy fluorescent microspheres and nitrocellulose membrane were used as carriers for labeling and coating CA19-9 pairing antibodies. We optimized the process by adjusting the amount of labeling and coating antibody. According to the linear range, lowest detection limit and precision, We evaluated the time-resolved fluorescence immunochromatographic assay of CA19-9. When the amount of labeled antibody was 80 μg for 20 μL fluorescent microspheres, and the concentration of coated antibody on the test line was 1.5 mg/mL, the optimal reaction time was 15 minutes. Assay linear range was 12.5 to 800 U/mL and the minimum detection limit was 6.32 U/mL. The Within-run and between-run coefficient of variation were less than 15%. Average recovery rate was 101%. By detecting 50 clinical samples in parallel with Roche electrochemical luminescence detection kit, correlation coefficient was 0.980 6. The experiment, initially established a fluorescence immunochromatographic detection method to quantitative detection of serum CA19-9, which has a good clinical application prospect.