Highly Efficient Dopamine Sensing with Carbon Nanotube Encapsulated Metal Chalcogenide Nanostructure

Abstract

Carbon nanotube encapsulated nickel selenide composite nanostructures were used as a non-enzymatic electrochemical sensor for dopamine detection. These composite nanostructures were synthesized through a simple, one-step, and environmentally friendly chemical vapor deposition method, wherein the CNTs were formed in situ from pyrolysis of carbon-rich metallo-organic precursor. The composition and morphology of these NiSe2 filled hybrid nanostructures were confirmed by powder X-ray diffraction, Raman, XPS, and HRTEM images. Electrochemical tests demonstrated that the as-synthesized nanostructures exhibited outstanding electrocatalytic performance toward dopamine oxidation, with a high sensitivity of 19.62 μA μM−1 cm−2, low detection limit, broad linear range of (5 nM – 640 μM), and high selectivity. The synergistic effects of enhanced electrochemical activity of nickel selenide along with enhanced conductivity of carbon nanotubes leads to the high efficiency for these nanostructured composites. The high sensitivity and selectivity of this nano-structured composite could be exploited to develop simple, selective, and sensitive electrochemical sensor to detect and quantify dopamine in human tear samples with high reliability. This nanotube encapsulated sensor hence paves the way for new discoveries in the development of novel dopamine sensors with low cost and high stability than can be used for non-invasive dopamine detection in peripheral fluids.