Single-Atom Ruthenium Biomimetic Enzyme for Simultaneous Electrochemical Detection of Dopamine and Uric Acid

Abstract

Single-atom catalysts have attracted numerous attention due to the high utilization of metallic atoms, abundant active sites, and highly catalytic activities. Herein, a single-atom ruthenium biomimetic enzyme (Ru-Ala-C3N4) is prepared by dispersing Ru atoms on a carbon nitride support for the simultaneous electrochemical detection of dopamine (DA) and uric acid (UA), which are coexisting important biological molecules involving in many physiological and pathological aspects. The morphology and elemental states of the single-atom Ru catalyst are studied by transmission electron microscopy, energy dispersive X-ray elemental mapping, high-angle annular dark field–scanning transmission electron microscopy, and high-resolution X-ray photoelectron spectroscopy. Results show that Ru atoms atomically disperse throughout the C3N4 support by Ru–N chemical bonds. The electrochemical characterizations indicate that the Ru-Ala-C3N4 biosensor can simultaneously detect the oxidation of DA and UA with a separation of peak potential of 180 mV with high sensitivity and excellent selectivity. The calibration curves for DA and UA range from 0.06 to 490 and 0.5 to 2135 μM with detection limits of 20 and 170 nM, respectively. Moreover, the biosensor was applied to detect DA and UA in real biological serum samples using the standard addition method with satisfactory results.

Nickel Cobaltite Nanoplate‐Based Electrochemical Sensing Platform from Printable Inks for Simultaneous Detection of Dopamine and Uric Acid

“…The LOD was calculated from the calibration curve using the equation LOD = 3.3σ/slope, where σ is the standard deviation of the slope. [1,9]…”

“…[4] Electrochemical biosensors have emerged as a promising analytical tool for realtime detection of biomolecules because of their ease of usage, cost-effectiveness, versatility, compact design, portability, reliable detection, easy operation, quick response, and stable output over other analytical methods. [5,9] There is surfeit literature related to the development of these electrochemical biosensors; however, the major drawback is enzymatic inhibition and degradation over time. Enzymatic sensor suffers from fouling issues, short and shelf-life, overlapping peak potentials that hinder the commercial use of fabricated electrodes.…”

“…[8] Xie and group fabricated single-atom ruthenium biomimetic enzyme electrodes supported on carbon nitride for contemporaneous detection of DA and UA with LOD of 20 and 170 nM. [9] Nanocomposites of transition-metal-based oxides on carbon support such as ZnO-graphene, [10] NiO-graphene nanosheets, [11] CuOgraphene, [12] and SnO 2 -graphene [13,14] have also been widely studied in literature due to their excellent properties like large surface area, porosity, high catalytic activity, fouling resistance, chemical, and mechanical stability, etc. However, metal oxidebased nanomaterials have issues related to the dissolution of metal ions, aggregation of nanoparticles, and Ostwald ripening, affecting their long-term stability despite their high performance.…”

Fabrication of Co3O4/NiCo2O4 Nanocomposite for Detection of H2O2 and Dopamine

“…Many biomolecules play an essential role in vital activities and biochemical reactions in the human body, such as transmitting biological molecules and responses in natural metabolism [1]. Common biological molecules are glucose [2], uric acid [3], RNA [4], ascorbic acid, hydrogen peroxide (H 2 O 2 ) [5], and dopamine [6,7]. The existence of these substances can maintain the normal physiological activities of the human body.…”

“…Once the concentration is too high, people may get schizophrenia. On the contrary, if dopamine concentration in the human body is too low, people may get depression [6,7]. H 2 O 2 concentration in some parts of the human body is also an important healthy index, which if sustained in a normal range, can keep human health [5,8,9]; therefore, it is very important to detect biological small molecules rapidly and accurately for disease diagnosis and clinic treatment [10,11].…”