Microfluidic paper-based analytical devices for reliable and low-cost point-of-care applications

Microfluidics allows analyzing small volumes of samples, which makes it an ideal technology to build a point-of-care device. Microfluidic paper-based analytical devices (μPADs) have been used on multiple applications. Paper is promising since colorimetric assays could be read with the naked eyed or a cell phone camera. Here we systematically tested several possible readers for bio-assays that use as a base a μPADs biosensors. Specifically, we tested digital imaging of an assay that produces a change of colors, imaging of a fluorescence-based assay, and an automatic scanning based on an in-house Multispectral-image Reconstruction System for colorimetric assays. We used commercial tests, both chemical and enzyme-based tests; as well as an in house test that used the emerging technology of DNA aptamers. Similarly, we evaluated the advantages and disadvantages of each setup and demonstrate how adaptable, fast, and versatile μPADs analysis can be. s. Finally, we suggest points of consideration to develop commercial point-of-care applications based on μPADs.