title: Size-selective QD@MOF core-shell nanocomposites for the highly sensitive monitoring of oxidase activities.
abstract: In this work, we proposed a novel and facile method to monitor oxidase activities based on size-selective fluorescent quantum dot (QD)@metal-organic framework (MOF) core-shell nanocomposites (CSNCPs). The CSNCPs were synthesized from ZIF-8 and CdTe QDs in aqueous solution in 40min at room temperature with stirring. The prepared CdTe@ZIF-8 CSNCPs , which have excellent water dispersibility and stability, displays distinct fluorescence responses to hole scavengers of different molecular sizes (e.g., H2O2, substrate, and oxidase) due to the aperture limitation of the ZIF-8 shell. H2O2can efficiently quench the fluorescence of CdTe@ZIF-8 CSNCPs over a linearity range of 1-100nM with a detection limit of 0.29nM, whereas large molecules such as substrate and oxidase have very little effect on its fluorescence. Therefore, the highly sensitive detection of oxidase activities was achieved by monitoring the fluorescence quenching of CdTe@ZIF-8 CSNCPs by H2O2produced in the presence of substrate and oxidase, which is proportional to the oxidase activities. The linearity ranges of the uricase and glucose oxidase activity are 0.1-50U/L and 1-100U/L, respectively, and their detection limits are 0.024U/L and 0.26U/L, respectively. Therefore, the current QD@MOF CSNCPs based sensing system is a promising, widely applicable means of monitoring oxidase activities in biochemical research.
authors: School of Chemistry and Chemical Engineering, Shaanxi Normal University, 620 West Chang'an Street, Xi'an 710119, China.
authors: Ke
authors: K
authors: Wang
authors: School of Chemistry and Chemical Engineering, Shaanxi Normal University, 620 West Chang'an Street, Xi'an 710119, China.
authors: Nan
authors: N
authors: Li
authors: School of Chemistry and Chemical Engineering, Shaanxi Normal University, 620 West Chang'an Street, Xi'an 710119, China; Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, 620 West Chang'an Street, Xi'an 710119, China.
authors: Jing
authors: J
authors: Zhang
authors: School of Chemistry and Chemical Engineering, Shaanxi Normal University, 620 West Chang'an Street, Xi'an 710119, China; Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, 620 West Chang'an Street, Xi'an 710119, China.
authors: Zhiqi
authors: Z
authors: Zhang
authors: School of Chemistry and Chemical Engineering, Shaanxi Normal University, 620 West Chang'an Street, Xi'an 710119, China; Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, 620 West Chang'an Street, Xi'an 710119, China. Electronic address: dangfqn@snnu.edu.cn.
authors: Fuquan
authors: F
authors: Dang
mesh_terms: D015374:Biosensing Techniques / Q000379:methods; D019187:Cadmium Compounds / Q000737:chemistry*; D057075:Enzyme Assays / Q000379:methods*; D005456:Fluorescent Dyes / Q000737:chemistry; D005949:Glucose Oxidase / Q000032:analysis / Q000378:metabolism*; D057230:Limit of Detection; D053761:Nanocomposites / Q000737:chemistry* / Q000648:ultrastructure; D009942:Organometallic Compounds / Q000737:chemistry*; D045663:Quantum Dots / Q000737:chemistry / Q000648:ultrastructure; D013050:Spectrometry, Fluorescence / Q000379:methods; D013691:Tellurium / Q000737:chemistry*; D014503:Urate Oxidase / Q000032:analysis / Q000378:metabolism*
chemical_list: D019187:Cadmium Compounds; D005456:Fluorescent Dyes; D009942:Organometallic Compounds; D005949:Glucose Oxidase; D014503:Urate Oxidase; D013691:Tellurium; C028337:cadmium telluride
keywords: Core-shell nanocomposites; Fluorescence; Oxidase activities; Size-selective