Nitrogen-Incorporated Ultrananocrystalline Diamond Electrodes for Dopamine Determination

Abstract

In this paper, nitrogen incorporated ultrananocrystalline diamond (NUNCD) films were fabricated for use as electrodes to detect dopamine. The NUNCD electrodes achieved high sensitivity, great selectivity, and excellent detection limits for dopamine sensing. The NUNCD electrode, fabricated as a potential sensitive biosensor for dopamine without any catalyst or mediators, demonstrated good activity for the direct detection of dopamine by simply putting the bare NUNCD electrode into a dopamine solution. Furthermore, the marked selectivity of the NUNCD electrode is very favorable for the determination of dopamine (DA) concentration (0.32 μM) in the presence of ascorbic acid (AA) and uric acid (UA). Considering dopamine detection in real biological fluid samples, the NUNCD electrode performed excellently with a detection limit of 0.39 μM and a high recovery ranging from 90-120%, revealing that NUNCD electrodes have promising use in the sensing of dopamine.

Nitrogen-Incorporated Ovoid-Shaped Nanodiamond Films for Dopamine Detection

“…The bonding of the CN species is strong, providing seeds for anisotropic grain growth, which explains the growth mechanism of the ovoid structure of the NOND. 27,28 NOND is a potential material for constructing sensitive biosensors for DA, which can directly sense DA in a solution containing DA, AA, and UA, 18 because the NOND film possesses polycrystalline grains with multiple orientations and amorphous carbon, thus the conductivity is enhanced as compared with the glassy carbon substrate. Moreover, the conductivity of the NOND film can be enhanced further via heterogeneous doping.…”

“…In this work, we aim to provide an in-depth investigation of the growth mechanism and study the sensing performance of the NOND film. Based upon the synthesis procedure that has been previously demonstrated to prepare highly sensitive and selective nanomaterials, a patterned NOND (P-NOND) film is synthesized, which creates a three-dimensional patterned structure to further improve the sensing properties. The potential for the use of this patterned structure in DA sensing is then investigated using an electrochemical measurement.…”

“…14,15 Moreover, the trans-polyacetylene sp 2 bonds and amorphous graphite structure at the grain boundaries of the NOND 16,17 enable NOND to detect the corresponding redox peaks of DA, AA, and UA. 18 However, very few studies have reported the growth mechanism of NOND films during the initial stages of the MPECVD process. In general, the presence of CN molecules in the plasma was adopted to explain the NOND growth process, and these molecules play a primary role in promoting the formation of the ovoid-shaped grains.…”

“…Nitrogen-incorporated ovoid-shaped nanodiamond (NOND) is a carbon material with excellent biomedical sensing properties, especially as it relates to DA sensing, owing to its excellent biocompatibility and protein adsorption capacity after special treatment. , Additionally, NOND possesses excellent chemical and mechanical properties, a wide working potential window (−1.5 to 1.5 V), and a low background current, which are advantageous for electrochemical sensing. , Through the incorporation of nitrogen into the structure in the microwave plasma-enhanced chemical vapor deposition (MPECVD) process, the sp 2 /sp 3 can be adjusted to a higher ratio so that the NOND films can exhibit high conductivity. , Moreover, the trans-polyacetylene sp 2 bonds and amorphous graphite structure at the grain boundaries of the NOND , enable NOND to detect the corresponding redox peaks of DA, AA, and UA …”

Human Exhalation CO2 Sensor Based on the PEI-PEG/ZnO/NUNCD/Si Heterojunction Electrode

“… 31 , 32 In particular, nitrogen-incorporated diamond films can increase the formation of sp 2 hybridization, which is beneficial in increasing the number of charge carriers. 33 NUNCDs have been used in several applications, especially in biosensors; 34 − 36 in this regard, the sensing surface area and the electrical conductivity are two key parameters to affect the sensor performance. A heterojunction semiconductor system can create more electron travel pathways due to the generation of electric fields at the interfaces.…”