Facile chemical modification of Nb2CTx MXene with ethylene diamine for sensitive electrochemical detection of dopamine from human serum samples

Abstract

• We present a facile method for the synthesis of aminated Nb 4 C 3 T x derivative through facile amination technique. • The amination of Nb 4 C 3 T x can enhance the electrochemical response • The aminated Nb 4 C 3 T x exhibited the highest sensing response towards dopamine in linear range of 1 nM – 100 μM. • The detection limit of the developed sensor reached as low as 300 pM. • The real sample analysis showed excellent agreement with the experimental results The electrochemical detection of dopamine (DA) is of ultimate importance in the early-stage diagnosis of Parkinson's and Alzheimer's diseases. In this work, we report the development of a facile amination technique of Nb 2 CT x MXenes for the electrochemical sensing of DA. The amination was confirmed using Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy the structural changes due to the amination process were confirmed using X-Ray diffractograms. The modified MXenes were used to modify carbon cloth electrodes, which were then applied to the electrochemical detection of DA. The developed sensor was able to detect dopamine linearly in the range 1 nM–100 μM and a limit of detection of (LOD) of 300 pM was achieved. The modified electrode was found to have a selective response to DA in the presence of other interferents in addition to being reproducible and stable. The modified electrode was also used for the detection of DA in serum samples with little difference in the sensing characteristics in phosphate buffer. This work presents a novel amination route for the surface functionalization of Nb 2 CT x and opens new avenues for applications of surface functionalized Nb-MXenes in electrochemical detection of neurotransmitters.