Validation and evaluation of a newly developed time-resolved fluoroimmunoassay for cyclosporine quantitative analysis in human whole blood

Abstract

Various immunoassay methods have been developed and used for the therapeutic drug monitoring (TDM) of cyclosporine (CsA). However, there is no report on the application of a time-resolved fluoroimmunoassay (TRFIA) in routine CsA TDM. The aim of this study was to evaluate the feasibility and validate the performance of a newly developed TRFIA method for CsA analysis in human whole blood. The TRFIA method was then compared with the method of chemiluminescent microparticle immunoassay (CMIA). The calibration range of the CsA-TRFIA method was 0–1000 ng/mL. The linear range and correlation coefficients were 30–1000 ng/mL and more than 0.990, respectively. The accuracy, precision, and inter-batch range were 90.0%–110.0%, less than 10%, and no more than 15%, respectively. The lowest limit of detection was less than 10 ng/mL. The linear regression equation was YCMIA = 0.961XTRFIA + 3.357, which showed that the measurements of CMIA and TRFIA were strongly correlated (r = 0.980). The results demonstrate that TRFIA is a precise and reproducible method for detecting the CsA concentration and can be used for routinely CsA TDM.