Colorimetric Detection of Uric Acid with High Sensitivity Using Cu2O@Ag Nanocomposites

Abstract

In this paper, we built the Cu 2 O@Ag nanocomposites-catalyzed 3,3′,5,5′-tetramethylbenzidine (TMB)-H 2 O 2 system for sensitive, rapid, and low-cost colorimetric sensing of uric acid (UA). Firstly, Ag nanotriangles were synthesized by dynamic method, and then Cu 2 O was encapsulated on the nanoflakes to synthesize Cu 2 O@Ag nanocomposites. Characterization of the structure and morphology of nanocomposites material were characterized by transmission electron microscopy, X-ray energy-dispersive spectroscopy, X-ray diffraction and X-ray photoelectron spectroscopy. Cu 2 O@Ag nanocomposites could catalyze the oxidation of TMB by H 2 O 2 (which is produced by enzymatic oxidation of UA), and the color changes from colorless to blue can be observed directly with the naked eyes or can be detected by UV-Vis spectrophotometer. The colorimetric sensor provided a linear absorbance response in the 0.5-100 μM UA concentration range with a 0.4 μM detection limit (S/N = 3). The recovery of UA in human serum by the proposed sensor is over 95.7%. Thus, these results imply that the UA sensor provides an effective tool in fast clinical analysis of gout without the need for expensive and advanced equipment.

High Performance NiOx Extended-Gate Field-Effect Transistor Biosensor for Detection of Uric Acid

“…On the other hand, it was found that the uricase immobilized on the EGFET biosensor showed a larger V REF than that without uricase, suggesting the presence of a negative charge in the uricase. 46 The sensing mechanism of an electrochemical uric acid biosensor involves an enzymatic reaction catalyzed by uricase, 10…”

“…9 Because it has a biologically active compound, uric acid is frequently interacted with the uricase on an electrode in an aqueous solution to produce allantoin, H 2 O 2 and CO 2 . 10 Since an ion-sensitive field-effect transistor (ISFET) was introduced by Bergveld 11 for neurophysiological measurements, various sensor devices, such as light-addressable potentiometric sensor (LAPS), extended-gate field-effect transistor (EGFET), nanowire field-effect transistor (FET), electrolyte-insulator-semiconductor (EIS), [12][13][14][15][16] have been developed and employed in different applications in clinical chemistry and laboratory medicine, food industry, industrial process control, environmental control, and chemical and biological warfare agents. Caras and Janata firstly proposed an enzyme FET device based on an ISFET sensor.…”

Developing Activated Carbon Veil Electrode for Sensing Salivary Uric Acid

“…Biosensors 2021, 11, 287 2 of 14 A variety of methods can be used to measure UA in biological fluids, including fluorescent [6], chromatographic with mass spectrometry, electrochemical and fluorescence detection [1,7,8], enzymatic colorimetric [9], capillary electrophoresis with electrochemical detection [10,11], and electrochemical [12,13]. These methods have both benefits and limitations.…”