Integration of a Smartphone Application with a ¼PAD for Rapid Colorimetric Detection of Glucose

Paper-based sensors have great potential for use in many different fields so far. In this study, a paper-based microfluidic analytical device (¼PAD) was integrated with a smartphone application capable of offline (no internet access) image processing and analysis for rapid colorimetric glucose detection. A paper towel was preferred due to its better water absorption efficiency than other papers. A stamp containing a 3D printed mold was used to form hydrophobic channels on a paper towel for the production of ADPAD. A hydrophobic by nature and light polymerizable resin was used as the ink. In order to increase the accuracy of the analysis, an image processing algorithm has been developed for the extraction of the region of interest (ROI) on the uPAD. The developed integrated platform gave a linear response in the range of 0.1 to 1 mM glucose and the limit of detection was calculated as 66.2 ¼M. The whole analysis was completed in less than one minute. Finally, a smart mobile phone application capable of offline image processing was developed to make the system user friendly. The integrated sensor system is portable, fast, user-friendly, ultra-low cost, usable by everyone, simple and sensitive.