Comparison of Carbon Nanomaterials for Simultaneous Detection of Neurotransmitters in the Presence of Interfering Species

Abstract

The main hurdle in simultaneous analysis of dopamine and serotonin is not only their similar detection potential but also the polymerization of dopamine at physiological pH, which results in sensitivity loss. In this work, we investigated glassy carbon electrodes and electrodes modified with carbon black, graphene oxide, and carbon nanodots in terms of their ability to detect 5 neurobiologically relevant analytes (dopamine, serotonin, epinephrine, norepinephrine, and 3,4‐dihydroxyphenylacetic acid). We proved that simultaneous detection of dopamine and serotonin in the presence of uric and ascorbic acids is possible on electrodes modified with carbon black and graphene oxide, both in buffer solution and cell medium. Graphene oxide‐modified electrodes have shown the highest sensitivity towards all tested neurotransmitters. Moreover, a considerable shift of epinephrine, norepinephrine, and 3,4‐dihydroxyphenylacetic acid peaks towards more negative potentials was observed for electrodes modified with carbon black and graphene oxide as compared with glassy carbon electrodes. Electrodes covered with carbon nanodots were proven inappropriate due to their surface functionalization with ethylenediamine.

Methods of Protection of Electrochemical Sensors against Biofouling in Cell Culture Applications

“…The solution was drop-cast on the electrode surface. Electrodes were left to dry and used on the next day …”

“…Electrodes were left to dry and used on the next day. 30 TMA and Tetramethoxysilane Silicate Matrix (TMA/ TMOS). 270 μL of TMOS with 30 μL of TMA, 75 μL of distilled water, 185 μL of methanol, and 5 μL of 11 M aqueous HCl were mixed and drop-casted on the electrode surface.…”

Detection of Dopamine Based on Aptamer-Modified Graphene Microelectrode

“…However, the electrochemical signal is weak when the conventional electrode is used to detect DA because of the slow electron transfer rate on the electrode surface. The electrode is modified by coating different materials, thereby overcoming the problem of a weak current signal and sensitively and rapidly detecting DA [8], such as carbon nanomaterials (including carbon black, graphene oxide, carbon quantum dots, and graphene quantum dots) [9], polymers [10], metal oxides (CuO, MnO 2 ) [11,12], metal nanoparticles (Au, Pd, Cu) [13][14][15], MOF materials [16,17], and so on.…”