Detection of pH/H2O2 and prostrate/breast cancer biomarker by using nickel-oxide/iridium-oxide sensing membrane in electrolyte-insulator-semiconductor structure

7^th Euro Biosensors and Bioelectronics Conference

July 10-11, 2017 Berlin, Germany

Siddheswar Maikap

Chang Gung University, Taiwan

Scientific Tracks Abstracts: J Biosens Bioelectron

Abstract :

Quantification of pH/H2O2 attracts a lot of attention due to its importance in chemical industries as well as biomedical diagnostic. For the detection of pH and H2O2, using electrolyte-insulator-semiconductor (EIS) is preferred due to label-free detection, easy fabrication process, and low cost. The NiOx based sensor has shown good pH sensitivity of 50.25 mV/pH. X-ray photo-electron spectroscopy of Ni 2p3/2 has shown two different oxidation states of NiOx membrane and those are Ni2+ and Ni3+ having binding energy 854.5 eV and 856.5 eV, respectively. Existence of these two oxidation states resembles the reduction-oxidation (redox) characteristics of NiOx membrane toward the electroactive species like H2O2. A reference voltage shift of 41 mV is obtained for H2O2 concentration of 10 �¼M and has shown good linearity up to 100 �¼M for the first time. In addition, the IrOx membrane shows a record pH sensitivity of 150.4 mV/pH for the first time. This IrOx sensor demonstrated good catalytic behavior as well as the breast cancer biomarker LOXL2 with a concentration of approximately 150 nM is detected. This IrOx nano-net sensor demonstrates good catalytic behavior for H2O2 reduction with a concentration of 100 fM because the oxidation state changes from Ir3+ to Ir4+, whereas a pure SiO2 membrane could not sense H2O2. The oxidation states are confirmed by X-ray photo-electron spectroscopy (XPS). Similarly, prostate cancer is also detected by using NiOx membrane. Therefore, good pH response and redox characteristics of the IrOx/NiOx sensing membrane allow it to diagnose human disease in future.

Biography :

Siddheswar Maikap has completed PhD in Department of Physics and Meteorology at IIT Kharagpur in February, 2003. He is Professor at Chang Gung University, Taiwan, since August 2014. He is the holder of three US patents on memory/bio-sensor, eight US/Taiwan patent files, and has more than 100 SCI journal papers, more than 150 international conference papers, 26 keynote/invited talks, and four best paper awards. His recent research focuses on cross-point resistive switching memory for high-density memory as well as bio-sensor applications.

Email: sidhu@mail.cgu.edu.tw