Porous Microneedle Integrated in Paper based Glucose Sensor for Fluid Channel Interface

Porous microneedles (MNs) are considered as promising methods to collect biosamples for painless and minimal invasive diagnosis of diseases such as diabetes. MNs have microscale size and interconnected pores and thus they can penetrate through epidermis without pain and collect interstitial fluid. These properties can be utilized for a new method for glucose sensing for diagnosis of diabetes. We thus focus on an integrated porous polydimethylsiloxane (PDMS)-based MNs (PDMS MN) with paper-based glucose sensor to realize the device for colorimetric diagnosis of diabetes. Disc-shaped PDMS MN layer consisting of 21 microneedles within an area of 1.7 cm2 was prepared. The microneedle showed a length of 800 μm and a porosity of 70 %. In this integrated system, porous media connects needles and sensor via a microfluidic channel. We successfully demonstrated the qualitative andquantitative analysis of glucose in the sample solution collected by porous MNs.