Stabilization of Horseradish Peroxidase Using Epoxy Novolac Resins for Applications with Microfluidic Paper-Based Analytical Devices

Abstract

Microfluidic paper-based analytical devices (microPADs) are an emerging platform for point-of-care diagnostic tests for use by untrained users with potential applications in healthcare, environmental monitoring, and food safety. These devices can be developed for a multitude of different tests, many of which employ enzymes as catalysts. Without specialized treatment, some enzymes tend to lose their activity when stored on microPADs within 48 hours, which is a major hurdle for taking these types of devices out of the laboratory and into the real world. This work focused on the development of simple methods for stabilizing enzymes by applying polymers to chromatography paper. The longterm stabilization was exlored and SU-8 of various concentrations was found to stabilize horseradish peroxidase for times in excess of two weeks. A variety of microPAD fabrications, enzyme dispensing methods, and substrate delivery techniques were explored.