A fluorescence point-of-care testing system for sample-to-answer detection of immunoglobulin E

In the work, a novel fluorescence point-of-care testing (POCT) system was developed for sample-to-answer detection of immunoglobulin E (IgE), which is the first time that a cloth material has been applied to the fluorescence detection of proteins. The system included an lateral/vertical flow-based microfluidic (LVFM) model, POCT detector, and smartphone-based data processing module. In the LVFM model, the non-woven cloth and screen-printing methods were applied to break the restrictions of traditional lateral flow strips on nitrocellulose membrane material and fabrication method. The 3D-printed POCT detector was used to supply a dark environment, with advantages of small volume, lightweight, and being easy-to-use. The smartphone-based data processing module was applied for image acquisition, image analysis and data display. After the fluorescent image was taken, the image analysis was carried out by the self-developed APP. By using the proposed POCT system, on the optimized conditions, the desired IgE detection was obtained, with a linear dynamic detection range of 10-1000 ng mL-1, and detection limit of 8.5 ng mL-1. In addition, the presented system showed good selectivity, repeatability and stability, and had the potential to be used in the field of detection of allergic diseases.