A CoOOH nanoflake-based light scattering probe for the simple and selective detection of uric acid in human serum

Abstract

In the presence of uricase, uric acid generated H2O2, which further decomposed CoOOH nanoflakes to release Co2+, resulting in smaller nanoparticles with lower light scattering. Based on the relationship between the reduced light scattering and uric acid concentration, the simple strategy was applicable to uric acid sensing in human serum samples.

Self-Assembled Monolayers on Screen-Printed Gold Electrodes for Uricase Enzyme Covalent Immobilization

“…Clearly, the AuNPs incorporation shifted the oxidation potential from 0.62 to 0.5 V due to a better electron transfer on the working surface (25), especially when compared with bare and activated AuSPE. The SAM formation dramatically increased the oxidation electrical current response towards UA, but retained oxidation potential at 0.5 V. Finally, the maximum response for UA was obtained with the Uox immobilized on the working surface, due to the enzyme catalytic reaction to oxidize the UA molecules (9). Once the AuSPE/SAM/Uox biosensor was fully developed, an UA detection assay at different concentrations was completed to obtain calibration data.…”

“…Due to their selectivity, enzymes are biological elements commonly used as bioreceptors [8]. Uricase (Uox) is an enzyme widely used as a bioreceptor for UA detection due to its catalytic action for UA oxidation, producing allantoin and carbon dioxide (CO2) as subproducts (9). The high Uox selectivity to UA molecules is crucial in the developing of sensor devices giving the presence of interferent analytes in biological fluids such as D-(+)-Glucose, ascorbic acid (AA), dopamine, cholesterol, paracetamol, among others (10).…”

Silver-Coated Gold Nanorods as Optical Probes for the Sensitive Detection of Ascorbic Acid in Tablets

“…The etching of silver-coated gold nanorods by •OH is susceptible to temperature. On the one hand, the elevated temperatures enhanced the formation of radical •OH [29]; on the other hand, H 2 O 2 is easy to decompose at a higher temperature [30]. As the reaction temperature increased, the blue shift of the longitudinal absorption wavelength was enhanced, which reached the stable state at 45 • C (Figure 5F).…”

Fluorescence wavelength shifts combined with light scattering for ratiometric sensing of chloride in the serum based on CsPbBr3@SiO2 perovskite nanocrystal composite halide exchanges

“…7 In addition to these ratiometric principles, light scattering has also been utilized to design ratiometric sensors with much higher simplicity. [8][9][10][11][12][13] Light scattering is observed not only at the incident wavelength but also at double and half of the excitation wavelength, resulting from second-order diffraction at the grating. The former is referred to as first-order scattering (FOS), while the latter is known as second-order scattering (SOS) and frequency doubling scattering (FDS), respectively.…”