3-D printed microfluidics for rapid prototyping and testing of electrochemical, aptamer-based sensor devices under flow conditions

Abstract

We demonstrate the ability to rapidly prototype and fabricate an epoxy-embedded electrode platform and microfluidic device suitable for using electrochemical biosensors under flow conditions. We utilize three-dimensional (3-D) printing to rapidly prototype molds to fabricate epoxy-embedded electrodes in addition to molds for rapid prototyping of PDMS microfluidic components. We characterize the bare gold epoxy-embedded electrodes using ferricyanide as a redox indicator and then characterize the performance of an adenosine triphosphate (ATP) specific electrochemical, aptamer-based (E-AB) sensor. We then incorporate the ATP specific E-AB sensors into the microfluidic device to study and take advantage of the dynamic response this class of sensor offers. We were able to flow varying concentrations of target analyte and monitor the dynamic response of the sensors to the changing concentration. This work demonstrates the ability to rapidly prototype E-AB sensors under flow conditions using 3-D printing which can lead to rapid and affordable point-of-care or fieldable applications where dynamic measurements of concentration, specificity and sensitivity and multiplex detection are necessary.

Keywords: 3-D printed microfluidic prototypes; Aptamer-based sensors; Dynamic concentration measurement; Electrochemical; Epoxyembedded electrodes.