POINT-OF-CARE TEST FOR C-REACTIVE PROTEIN BY A FLUORESCENCE-BASED LATERAL FLOW IMMUNOASSAY

摘要

An innovative, portable fluorescence reader was developed for the determination of C-reactive protein based on a lateral flow immunoassay. The C-reactive protein concentration was proportional to the intensity of the test line which was calibrated relative to the control line. To quantify the fluorescence intensity of the lateral flow strip, a custom illumination module, which concentrated the excitation beam from an ultraviolet light-emitting diode, was developed for strip scanning. Accordingly, a high sensitive photodiode with a preamplifier was chosen as the detector for fluorescence. For good repeatability, the strip scanning resolution was set to 5 mu m between data points by controlling a linear stage actuated by a stepper motor. Four double-logistic calibration models were compared. The sensitivity for C-reactive protein was 0.1mg/L and the linear dynamic range extended to 400mg/L. The optical reader provides a new and simple approach for the determination of C-reactive protein and may be modified for other similar biomarkers.