pH sensor using protein-mediated gold nanocrystal array

pH sensitivity of protein mediated gold nanocrystals modified SiO
₂
have been investigated using a capacitive EIS (electrolyte-insulator-semiconductor) structure and compared with bare SiO
₂
. The SiO
₂
surface was first silanized using phenyltriethoxy and then a chaperonin protein array was formed on SiO
₂
surface. Finally, the chaperonin protein lattice is used to deposit gold nanocrystal on SiO
₂
surface in the EIS structure. The electrochemical characterization of EIS sensors was done by means of C-V measurement in pH buffer solutions of values from 2 to 12. The average sensitivity of gold modified SiO
₂
senor was 33 mV/pH and SiO
₂
senor was 35 mV/pH while the linearity was 99.37% and 98.35%, respectively.