A low-cost mobile platform for whole blood glucose monitoring using colorimetric method

In this work, we present a portable low-cost point-of-care (POC) blood glucose monitoring system, which is composed of an additively manufactured smartphone-based optical detection platform and a disposable paper based glucose colorimetric detection device. To improve the uniformity of color development and manufacture efficiency, the disposable micro paper-based device (mu PAD) was functionalized and mass-produced by inkjet printing of colorimetric assay 3,3 ',5,5 '-Tetramethylbenzidine (TMB) substrate and glucose oxidase/horseradish peroxidase (GOx/HRP) bi-enzymatic system on the sensing zone. The separation of plasma from blood was achieved by the membrane filter laminated on the top of the sensing zone. A 3D printed smartphone-based optical detection platform enables the facile readout and analysis of glucose detection by avoiding the influence of intensity from the variation of ambient light. This POC system has been demonstrated to successfully determine a wide range of blood glucose (0.5-2.84 mg/ml) with limit of detection as 5 mg/dl (0.28 mM). The detection of blood glucose directly from human whole blood samples was performed. Our results showed relative errors ranging from 4.37% to 14.41% compared with a spectrophotometry method, and 3.83%-14.53% compared with a commercial glucose meter. With a combination of advantages of low-cost, high reliability and high fabrication efficiency, this system has the great potential to be a competitive method for POC glucose monitoring, especially for patients in underserved communities.