Inkjet printing on transparency films for reagent storage with polyester-toner microdevices

Abstract

The use of overhead transparencies as substrates for the fabrication of microfluidic devices brings new capabilities in the creation of fully-integrated systems. Here, we describe a reagent storage method through inkjet printing that is complementary to the simple print, cut and laminate (PCL) fabrication technique, which already incorporates printing toner onto commercial off-the-shelf materials for fabrication of polyester-toner microdevices. With the surface of the polyester film dramatically different than paper, substrate optimization was required to increase printability without incorporating additional substrate-coating steps. Functionality for chemical sensing devices, operated centrifugally here, was demonstrated through standard human serum albumin analysis. Quantitative results were obtained through image analysis using a desktop scanner to determine color change in the presence of various total protein and albumin concentrations. Printed devices exhibited a shelf life of at least two months with no loss in activity, resulting in a relative standard deviation of 0.652% for total protein analysis.