Sensitive ratiometric fluorescence assay for detecting xanthine in serum based on the inner filter effect of enzyme-catalyzed oxidation products to silicon nanoparticles.

Sensitive ratiometric fluorescence assay for detecting xanthine in serum based on the inner filter effect of enzyme-catalyzed oxidation products to silicon nanoparticles. Anal Bioanal Chem. 2021 Jan 02;: Authors: Li D, Chen F, Li N, Ye X, Sun Y, Ma P, Song D, Wang X Abstract A new type of fluorescent silicon nanoparticles (SiNPs) were prepared via a facile one-pot hydrothermal method by using N-[3-(trimethoxysilyl)propyl]-ethylenediamine (DAMO) and glucose as reagents, and were subsequently applied to construct a ratiometric fluorescence assay for sensitive and rapid determination of xanthine in human serum. Two catalytic oxidation reactions were employed to induce a fluorescence response of the testing system towards xanthine. Under the catalysis of xanthine oxidase (XOD), xanthine in serum samples was oxidized and produced hydrogen peroxide (H2O2). By utilizing o-phenylenediamine (OPD) as the substrate for horseradish peroxidase (HRP) in the presence of H2O2, fluorescent 2,3-diaminophenazine (DAP) was finally generated. A ratiometric fluorescence assay for xanthine was established by determining the ratio of the green-yellow fluorescence emission of DAP and the blue fluorescence emitted from SiNPs under the inner filter effect (IFE) of DAP. Instead of traditional multi-step procedures for adding reacting reagents to the testing solution, all the reaction reagents were mixed with serum samples in a single step for this assay to sho...
Source: Analytical and Bioanalytical Chemistry - Category: Chemistry Authors: Tags: Anal Bioanal Chem Source Type: research