Flexible rolled thick-film miniaturized flow-cell for minimally invasive amperometric sensing

We describe here a miniaturized flexible thick-film electrochemical biosensor flow detector, suitable for insertion into the lacrimal canaliculus towards minimally invasive amperometric monitoring of biomarkers in the tear fluid. Our focus here is on the microfabrication and in-vitro testing of the new laterally rolled screen-printed sensor. The new device responds rapidly and sensitively to dynamic changes in the levels of norepinephrine and glucose (the later in connection to glucose-oxidase containing ink). Coverage of the enzyme electrode with an electropolymerized polytyramine minimizes contributions from the common electroactive interferences ascorbic and uric acids. Such attractive performance indicates great promise for minimally invasive monitoring of health biomarkers in the tear fluid, or in alternative usage such as capillary microelectrophoresis, ultralow volume sampling, or in-flow (tubular) systems for batch processing of blood or culture media.