Stamping of Microfluidic Paper-based Analytical Devices with Chemically Modified Surface for Clinical Diagnostics

We describe the development of a handheld stamp for the production of microfluidic paper-based analytical devices. The paper surface was oxidized for allowing the covalent coupling of enzymes. The chemical modification led to improvements on the color uniformity. The relative standard deviation values for glucose and uric acid assays decreased from 40 to 10% and from 20 to 8%, respectively. The semi-quantitative analysis of target analytes in artificial urine sample revealed an error smaller than 4%. The disposability, the low cost of devices and the better color uniformity enable the use of the proposed devices for the point-of-care diagnostics.