ZnO Based Microfluidic pH Sensor: A Versatile Approach for Quick Recognition of Circulating Tumor Cells in Blood.

Research paper by Ganesh Kumar GK Mani, Madoka M Morohoshi, Yutaka Y Yasoda, Sho S Yokoyama, Hiroshi H Kimura, Kazuyoshi K Tsuchiya

Indexed on: 25 Jan '17Published on: 25 Jan '17Published in: ACS Applied Materials & Interfaces


The present study is concerned about the development of highly sensitive and stable microfluidic pH sensor for possible identification of circulating tumor cells (CTCs) in blood. The precise pH measurements between silver-silver chloride (Ag/AgCl) reference electrode and zinc oxide (ZnO) working electrode have been investigated in the microfluidic device. Since there is a direct link between pH and cancer cells, the developed device is one of the valuable tools to examine the circulating tumor cells (CTCs) in blood. The ZnO based working electrode was deposited by radio frequency (RF) sputtering technique. The potential voltage difference between the working and reference electrodes (Ag/AgCl) is evaluated on the microfluidic device. The ideal Nernstian response of -43.71165 mV/pH was achieved along with high stability and quick response time. Finally to evaluate the real time capability of the developed microfluidic device, in vitro testing were done with A549, A7r5 & MDCK cells.