Fabrication of dopamine sensor based on ternary AlMn0.645Cr1.76O7.47 nanoparticles

Abstract

A reliable and highly sensitive dopamine sensor was fabricated with mixture of Al–Mn–Cr-oxide (the composition is found as AlMn0.65Cr1.76O7.47) nanoparticles (NPs). The wet-chemically synthesized NPs was deposited onto a glassy carbon electrode (GCE) as a layer of thin film using conductive 5% Nafion suspension in ethanol as a chemical binder. The assembled AlMn0.65Cr1.76O7.47 NPs/binder/GCE sensor was selective towards dopamine and was implemented to analyze a number of dopamine solutions with various concentration. The electrochemical response of the sensor was found to be indifferent to the presence of electrolytes like Na+, K+, Ca2+ and Fe2+ in the analyte-samples. The electrochemical response of the sensor was reproducible in replicate runs at a single time of use as well as in usage at different time-intervals. The I vs. logC plot was linear over a range of as wide as 0.1 nM- 0.01 mM. The sensitivity of the assembled electrode at the applied potential +1.5 V was found to be 55.8165 μAμM−1cm−2, while the detection limit was 96.87 ± 4.84 pM. The fabricated sensor was detected the dopamine effectively and measured it in the real biological samples precisely. Thus, the present approach to developing sensors has acquired immense potential significance for future application in biomedical sector.