Nanocomposite Materials based on Metal Nanoparticles for the Electrochemical Sensing of Neurotransmitters

Abstract

Neurotransmitters (NTs) are known as endogenous chemical messengers with important roles in the normal functioning of central and peripheral nervous systems. Abnormal levels of certain NTs, such as dopamine, serotonin and epinephrine, have been linked with several neurodegenerative diseases (such as Alzheimer’s disease, Parkinson’s disease and Huntington’s disease). To date, various strategies have been employed for the quantitative determination of NTs, and nanocomposite materials based on conducting polymers and metal nanoparticles constitute a cornerstone for the development of electrochemical sensors with low costs, stability, fast response rates and high selectivity and sensitivity. The preparation and analytical applications of nanocomposite materials based on metal nanoparticles in the electrochemical sensing of neurotransmitters are discussed in this paper. Recent developments in the electrochemical sensing of neurotransmitters are also discussed with emphasis on the benefits brought by metal nanoparticles in improving the sensitivity of the analytical measurements. The electrochemical synthesis methods for the in situ generation of metal nanoparticles within conducting polymer layers are reviewed. The analytical applications of the nanocomposite-sensing materials towards the detection of neurotransmitters such as dopamine, epinephrine and serotonin are discussed in terms of detection and quantification limits, linear response range, sensitivity and selectivity.