To achieve a dopamine(DA)response with high sensitivity and high signal-to-noise ratio(S/N)with a patch-clamp system,polypyrrole/graphene(PPy/GR)nanocomposites were steadily electrodeposited by an electrochemical method on a planar microelectrode array(pMEA)fabricated by a standard micromachining process.The electrodeposition process was carried out by chronopotentimetry measurement scanning from 0.1 to 0.8 C/cm2at the current of 2 mA;0.5 C/cm2was found to be optimal.The pMEA modified by PPy/GR at the 0.5 C/cm2exhibits remarkable properties;for instance,the standard deviation(SD)decreases from 8.4614×10-11to 5.62×10 11A,reduced by 33.52%,and the sensitivity increases from 2566.88 to 76114.65μAmMcm-2,29.65 times higher than the bare Pt(platinum).A good linear relationship between the current and DA concentration in the range of 0.30 to 61.71μm was obtained,with a correlation coefficient of 0.997.The sensor is meaningful for neuroscience research and the treatment of neurological diseases.
WANG LiJIANG TingJunSONG YiLinSHI WenTaoCAI XinXia
