Microthermopiles integrated with fluidic channels as calorimetric MEMS biosensors

This paper presents the fabrication and preliminary performance characteristics of a calorimetric MEMS biosensor. The sensor consists of freestanding microthermopiles integrated with polymeric microfluidic channels. The fabricated microthermopiles on a freestanding nitride-oxide-nitride membrane have a responsivity of 1.8 V/W and a time constant of less than 100 ms. Continuous flow testing was performed with hot water a evaluate the performance of the sensors. Measurements of the heat of reaction from the oxidation of glucose catalysed by glucose oxidase enzyme were performed using an open channel configuration. These measurements indicate that the up to 1 mM (1 nmole) sensitivity can be achieved using the sensor in open channel configuration.