LED&Paper-based analytical device for phosphatemia/calcemiadiagnostics

tIn this communication a prototype of paper-based analytical device designed for simultaneous deter-mination of orthophosphate and calcium ions, which levels are significant for hyperphosphatemiadiagnostics, is presented. The laboratory-on-paper structure for two analytes detection was wax-printedon the surface of filter paper. These two-analyte disposable paper strips are combined with two pairedLED-based fluorescence detectors and simple voltmeter used as recorder of analytical signal, what makesthe developed device miniature, extremely low-cost, portable and user-friendly. Thus the developeddevice allows usage outside of specialized clinical laboratory. Moreover, each paper strip is disposableand its utilization is easy and fast and, additionally, burnt strip tests ensure waste non-infectious. Thepresented LED&Paper-based analytical device provides low detection limits: 1.4 mol L−1and 7.4 molL−1for orthophosphate and calcium ions, respectively. The practical utility of the developed devicefor calcemia/phosphatemia diagnostics is demonstrated using control serum standards and real humanserum.