Adsorption properties of dopamine derivatives using carbon nanotubes: A first-principles study

Abstract

Detecting dopamine is of great biological importance because the molecule plays many roles in the human body. For instance, lack of dopamine release is the cause of Parkinson's disease. Although many researchers have carried out experiments on dopamine detection using carbon nanotubes (CNTs), there are only a few theoretical studies on this topic. We study the adsorption properties of dopamine and its derivatives, L-DOPA and dopamine o-quinone, adsorbed on a semiconducting (10, 0) CNT, using density functional theory calculations. Our computational simulations reveal that localized states originating from dopamine o-quinone appear in the bandgap of the (10, 0) CNT, but those originating from dopamine and L-DOPA do not appear in the gap. Therefore, dopamine oquinone is expected to be detectable using an external electric field but dopamine and L-DOPA should be difficult to detect.

Band Gap Engineering toward Semimetallic Character of Quinone-Rich Polydopamine

“…The relations observed in the UV–vis spectra and electrochemistry can be better understood through the analysis of the DOS plots of different PDA structural units (Figure ). First, the HOMO–LUMO gap is equal to 3.4–3.8 eV for catecholic units (DA, LDC, and DHI) and there are only slight differences between them . Considering that the XPS spectra coupled with the electrochemistry and DFT adsorption simulations showed that a-PDA consists mainly of catecholic units, its high HOMO–LUMO gap is responsible for the negligible effects on the UV–vis characteristics (Figure a–c) and reduced photoactivity.…”

Loofah activated carbon with hierarchical structures for high-efficiency adsorption of multi-level antibiotic pollutants

“…From the formula for adsorption energy (Equation 8), the Ead were calculated to be of -0.397, -0.629 and -0.385 eV (the calculated results are listed in Table S2) for LAC-TC, LAC-OFO and LAC-NFO, respectively. The probe atom is preferentially adsorbed on the sites with the lowest adsorption energy, [70][71] which means that the adsorbates are prone to be adsorbed on LAC with the order of OFO ＜ TC ＜ NFO. Therefore, the calculated results are in good agreement with the adsorption capacities following the order of OFO ＞ TC ＞ NFO.…”

Carbon Nanotube Electrodes for Electrochemical Detection of Dopamine

“…Given the higher basal concentration and chemical relatedness of DOPAC it is likely that DOPAC is predominantly detected over dopamine. DFT studies have shown that CNT electrodes have higher affinity for DOPAC than dopamine 42 . We tested this hypothesis by exposing our electrodes to known concentrations of DOPAC and found that DOPAC is oxidized at 0.5V and reduced at 0.1V ( Figure 3C ).…”