Probe Sensor Using Nano-Structured Multi Walled Carbon Nanotube Yarn for Direct Selective and Sensitive Dopamine Detection

Abstract

Dopamine (DA) is an important neurotransmitter in the central nervous system. Insufficient or excessive level of DA related to Schizophrenia and Parkinson diseases[ 1 ]. Therefore, early detection of DA represents a hot topic in biosensing field. Recently, electrochemical bio-sensor (ECB) based on carbon material has received a great attention as an inexpensive and simple analytical method with remarkable detection sensitivity for neurochemicals detection[ 1 ]. Therefore, ECB’s fabrication and structure have attracted researcher’s efforts to obtain higher sensitivity and highly selectivity simultaneously. Traditional film-based ECB have shown some disadvantages such as large sizes, random structure, time consuming for film fabrication and low efficient[ 2 ]. As a result, a new biosensor based on nano carbon material designed in a probe style has been considered as an excellent candidate for sensing stimulation as they have aligned and packed structure which provides a bridge for electrons transfer and that enhances electrical conductivity, also, fibres can be fabricated in small sizes which gives the ability to be implanted with low tissue damages, in addition, simplicity of handling and ability to be grafted with different materials[ 3 ]. The aim of this study is to develop hybrid multi wall carbon nanotube yarn due to fascinating properties for CNTs (i.e. high surface area, fast electron kinetics transfer, reduced electrode fouling, wide electrochemical potential window, bio-compatibility, grafting ability, and increased sensitivity and selectivity (high efficient)). In a typical bio-sensing system, DA has been used with ascorbic acid (AA) and uric acid (UA) (as coexistence compounds[ 4 ]) for investigating both sensitivity and selectivity of the prepared CNT yarn viacyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques. CV and DPV results have demonstrated selective and sensitive detection of DA in a sea of AA and UA with the potential to be a promising probe bio-sensor for real-time measurement.