Rapid prototyping of a flexible microfluidic sensing system using inkjet and screen printing processes

A novel microfluidic sensing system (MSS), for the detection of bio/chemicals, has been successfully developed. Screen printing process was employed, as an additive manufacturing method, to create master molds for fabricating polydimethylsiloxane (PDMS) based microfluidic channels. Silver (Ag) ink was inkjet printed on flexible polyethylene terephthalate (PET) substrate, to form interdigitated electrodes (IDE). The MSS was created by bonding the PDMS based microfluidic channels and printed PET substrate. The electrochemical impedance spectroscopy (EIS) based response of the MSS towards heavy metal compounds: cadmium sulfide (CdS) and mercury sulfide (HgS), revealed picomolar concentration detection levels. The results obtained also demonstrated the capability of using inkjet and screen printing processes for the rapid prototyping of MSSs. The response of the developed MSS is analyzed and presented in this paper.