Evaluation of a time-resolved fluorescence immunochromatography for procalcitonin

Objective To evaluate the performance of a time-resolved fluorescence immunochromatographic assay for quantitative detection of procalcitonin (PCT). Methods Based on double antibody sandwich method and using time-resolved fluorescent nano-microspheres as the marker, we established an immunochromatographic assay for detecting PCT. We evaluated the performance of this method for PCT detection in terms of linearity, sensitivity, precision, specificity, and correlation. Results This immunochromatographic assay had a good linearity for PCT detection within the linear range of 0.05-100 ng/mL, and the linear equation was Y=0.074 7X+0.524 6 (R2=0.990 4). The sensitivity of this method was 0.03 ng/mL with an inter-assay precision CV≤5.42% and an intra-assay precision CV≤6.86%. The detection results by this method were well correlated with those by AE-180 automatic chemiluminescence immunoanalyzer and showed a positive coincidence rate of 96.61% and a negative coincidence rate of 94.44%; The false positive rate, false negative rate and diagnostic coincidence rate of this assay were 5.56%, 3.39%, and 95.53%, respectively. Conclusion This time-resolved immunochromatographic assay allows simple, economic, rapid and quantifiable detection of PCT and shows a good performance for potential application in the detection for clinical serum samples.