Diagnostics devices for improving the world: μPADs integrated with a smartphone for colorimetric detection of dopamine

A simple, inexpensive, reliable, portable, and environmentally friendly colorimetric method was developed to determine DA concentrations, In this research, colorimetric detection of dopamine (DA) was proposed on fast, simple, sensitive and low-cost μPADs, which is fabricated by using laser cutting technique. For this purpose, a Whatman® Filter paper No.1 was used as an analytical substrate. In paper-based microfluidic systems, wax printing is commonly used to create a hydrophobic barrier, but in this study, labels were used for the first time to create hydrophobic barriers due to their cost-effectiveness and easy access. The presence of DA made the red color bolder, and quantitative amount was obtained by taking picture from the colored areas with a smartphone and using Photoshop software. This method demonstrates the potential for detection without equipment because the chemical reaction can only be seen on paper with naked eyes. The analytical platform is made of cellulosic material that is compatible with many chemicals, and it is easy to use and can be easily stored