Measurement of Neuropeptide Y Using Aptamer-Modified Microelectrodes by Electrochemical Impedance Spectroscopy

Aptamer-modified microelectrodes for Neuropep-tide Y measurement by electrochemical impedance spectroscopy was described here. The advantages of using carbon fiber or platinum microelectrodes are because they are promising materials with high electrical conductivity, chemical stability, and high surface area that can be easily modified on their surface. The immobilization and biofouling were studied and compared using EIS. Moreover, the adsorption of NPY to the aptamer-modified microelectrodes was also demonstrated by EIS. Changes of -omega*Z(imag), an impedance factor that gives information of the capacitance, is directly correlated with concentrations. A widely linear range was obtained from 10 to 1000 ng/mL of NPY. This method was able to detect NPY without performing a redox reaction by adsorption at the surface of the microelectrodes, with the specificity provided by aptamer functionalization of the microelectrode surface.

Automated summary

The study demonstrated the measurement of Neuropeptide Y using aptamer-modified microelectrodes by electrochemical impedance spectroscopy. The method showed high sensitivity, specificity, and a wide linear range for NPY detection without the need for a redox reaction. The immobilization and biofouling of the microelectrodes were studied and compared, with changes in impedance factors directly correlated with NPY concentrations.