Functionalized multi-walled carbon nanotube/silver nanoparticle (f-MWCNT/AgNP) nanocomposites as non-enzymatic electrochemical biosensors for dopamine detection

Abstract

Dopamine (DA) is an important neurotransmitter in the kidney, cardiovascular system, and central nervous system, which abnormality is associated with many diseases. In this work, we synthesized a functionalized multi-walled carbon nanotube/silver nanoparticle (f-MWCNT/ AgNP) nanocomposites as the biosensing material to detect DA. The SEM, EDS, and TEM characterizations indicated the success of the functionalization process with MWCNT as the base material. The values of the linear range, the limit of detection (LOD), and the selectivity of the nanocomposite were all obtained from the Differential Pulse Voltammetry (DPV) measurements. The obtained LOD value was 0.2778 mM in the linear range of 0-8 mM, which is lower than the required concentration value for detecting DA in human urine (0.3-3 mM). The biosensor's high selectivity on DA with the presence of other human-related biofluids was also reported. These results show that f-MWCNT/AgNP nanocomposites are a promising biosensor material for the detection of DA.

Chronoampermetric detection of enzymatic glucose sensor based on doped polyindole/MWCNT composites modified onto screen-printed carbon electrode as portable sensing device for diabetes

“…Electrode modification with MWCNTs composites yields long-term stability and selectivity for biosensors as a result of its potential synergistic effects. 36 Most biosensors based on conductive polymers were fabricated by electrochemical polymerization as it provides a better control of polymer deposition. 37 However, this technique requires time for preparation and it is difficult to prepare in large quantities.…”

An ultra-sensitive uric acid second generation biosensor based on chemical immobilization of uricase on functionalized multiwall carbon nanotube grafted palm oil fiber in the presence of a ferrocene mediator

“…2b), which indicates that the introduction of the COOH group in MWCNT doesn't affect the crystallinity of the native structure. 26,27 The diffractogram of NaOH-POF is given in Fig. 2c, where a characteristic peak seen at 2q = 22.18°corresponds to the d(002) plane for cellulose.…”

Recent Developments in the Design and Fabrication of Electrochemical Biosensors Using Functional Materials and Molecules

“…SACNT was incorporated due to its high conductivity, huge surface area, excellent electrocatalytic area, and large contact area for the analytes to interact. In another attempt, a dopamine (DA) biosensor was developed using silver nanoparticle-decorated FMWCNTs-modified GCE, which showed a LOD of 0.277 µM in 0.01 M phosphate buffer [ 73 ]. Pal and Majumder developed a label-free biosensor for the ultra-low detection of silver ions using an ssDNA-functionalized MWCNTs-modified AuE via cytosine–cytosine mismatch chemistry [ 74 ].…”