Facile and controllable synthesis of monodisperse gold nanoparticle bipyramid for electrochemical dopamine sensor

Abstract

We demonstrated potential features of gold nanoparticle bipyramid (AuNB) for an electrochemical biosensor. The facile synthesis method and controllable shape and size of the AuNB are achieved through the optimization of cetyltrimethylammonium chloride (CTAC) surfactant over citric acid ratio determining the control of typically spherical Au seed size and its transition into a penta-twinned crystal structure. We observe that the optimized ratio of CTAC and citric acid (CA) facilitates flocculation control in which Au seeds with size as tiny as ~14.8 nm could be attained and finally transformed into AuNB structures with an average length of ~55 nm with high reproducibility. To improve the electrochemical sensing performance of a screen-printed carbon electrode (SPCE), surface modification with AuNB via distinctive linking procedures effectively enhanced the electroactive surface area by 40%. Carried out for the detection of dopamine (DA), a neurotransmitter frequently linked to the risk of Parkinson’s, Alzheimer’s, and Huntington's diseases, the AuNB decorated-carbon electrode shows outstanding electrocatalytic activity that improves sensing performance, including high sensitivity, low detection limit, wide dynamic range, high selectivity against different analytes, such as ascorbic acid (AA), uric acid (UA) and urea, and excellent reproducibility.

Review—Catalytic Electrochemical Biosensors for Dopamine: Design, Performance, and Healthcare Applications

“…Lu et al 164 deposited WO 3 -SnO 2 nanoflakes onto a fluorine-doped tin oxide platform, achieving an very low LOD of 0.8 nM and significant linear range of 5 nM-1.75 μM in PBS. Rizalputri et al 165 deposited gold nanobipyramids on a SPCE, achieving an LOD of 37 nM and an increased linear range of 0.1-100 μM. Although this design allows for a wider working range, the biosensor lacks the ability to measure dopamine reliably at concentrations lower than 100 nM.…”

Breaking Barriers: Exploring Neurotransmitters through In Vivo vs. In Vitro Rivalry

“…Nonetheless, with diligent training and a meticulous approach, FSCV evolves into a potent instrument for scrutinizing neurotransmitter dynamics in states both normative and pathological. Notably, the advent of advanced tools has demonstrated FSCV’s aptitude for detecting neurotransmitters at low concentrations [ 24 , 25 , 26 , 27 , 28 ]. Moreover, FSCV exhibits compatibility with other techniques, exemplified by its synergy with Raman Spectroscopy, culminating in a hybrid sensing platform that merges spectral and electrochemical data of the sample [ 29 , 30 ].…”

Highly sensitive amperometric sensors based on laccase-mimetic nanozymes for the detection of dopamine

“…10 However, due to the high cost of laccase and its nonsufficient stability (susceptibility to changes of pH and temperature during the storage) it is advantageous to substitute laccase by nanoparticles (NPs) possessing laccase-like activity. [11][12][13][14][15] A number of low-cost laccase-like nanozymes NZs possessing high catalytic activity have been described and used for the development of DA-sensitive sensors, in particular, nanoparticles of Ni, 16 Pd, 17 Co, 18 Au, 19 Cu, 20 different nanooxides and suldes (FePt-Fe 3 O 4 , Fe 3 O 4 , Au@Fe 3 O 4 , ZnFe 2 O 4 , MoS 2 ), some polymers, carbon nanomaterials (single-walled nanotubes, multi-walled nanotubes) and carbon-based materials functionalized with metal NPs. [21][22][23][24][25][26] Detection of DA by electrochemical methods is not an easy task and is complicated by other redox biomolecules that can be oxidized at similar potentials, such as ascorbic acid or uric acid.…”