title: Sensitive fluorescent detection of H2O2and glucose in human serum based on inner filter effect of squaric acid-iron(III) on the fluorescence of upconversion nanoparticle.
abstract: Diabetes mellitus is an epidemic disease that it has became a worldwide public health problem. Thus, blood glucose monitoring has attracted extensive attention. Here, we report a nanosensor based on inner filter effect (IFE) between upconversion nanoparticles (UCNPs) and squaric acid (SQA)-iron(III) for the highly sensitive and selective detection of glucose levels in human serum. In this assay, GOx-catalyzed oxidization of glucose produces gluconic acid and hydrogen peroxide (H2O2). The latter can catalytically oxidize iron(II) to iron(III) which can rapidly (<1min) coordinate with the SQA to produce (SQA)-iron(III). The absorption band of (SQA)-iron(III) largely covered the emission band of UCNPs, resulting the fluorescence emission of UCNPs was effectively quenched. Therefore, the glucose can be monitored based on the formation of SQA-iron(III). Under the optimal condition, the fluorescence quenching efficiency shows a good linear response to glucose concentration in the ranges of 7-340μmol/L with a detection limit of 2.3μmol/L. The developed method has been further applied to monitor glucose levels in human serum with satisfactory results. Compared with other fluorescence methods, current method displayed high sensitivity and signal-to-noise ratio. Meanwhile, this nanosystem is also generalizable and can be easily expanded to the detection of various H2O2-involved analytes.
authors.affiliation: Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education), College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081, PR China.
authors.forename: Hongyu
authors.initials: H
authors.lastname: Chen
authors.affiliation: Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education), College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081, PR China.
authors.forename: Aijin
authors.initials: A
authors.lastname: Fang
authors.affiliation: Hospital of Hunan Normal University, Hunan Normal University, Changsha 410081, PR China.
authors.forename: Li
authors.initials: L
authors.lastname: He
authors.affiliation: Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education), College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081, PR China. Electronic address: zhangyy@hunnu.edu.cn.
authors.forename: Youyu
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education), College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081, PR China.
authors.forename: Shouzhuo
authors.initials: S
authors.lastname: Yao
mesh_terms: D001786:Blood Glucose / Q000032:analysis*; D003503:Cyclobutanes / Q000737:chemistry*; D005374:Filtration; D006801:Humans; D006861:Hydrogen Peroxide / Q000097:blood*; D007501:Iron / Q000737:chemistry*; D057230:Limit of Detection; D053758:Nanoparticles / Q000737:chemistry*; D013050:Spectrometry, Fluorescence / Q000379:methods*
chemical_list: D001786:Blood Glucose; D003503:Cyclobutanes; D006861:Hydrogen Peroxide; D007501:Iron; C030042:squaric acid
keywords: Glucose; H(2)O(2); Inner filter effect; SQA-iron(III); Upconversion nanoparticles