Xue Gao

Name: 高雪; Xue Gao

Organization: Bohai University , China

Department:

Title: Lecturer(PhD)

Chemicals
References

Sensitive fluorescence assay of organophosphorus pesticides based on the fluorescence resonance energy transfer between CdTe quantum dots and porphyrin

Co-reporter:Gao Xue, Zhao Yue, Zhang Bing, Tang Yiwei, Liu Xiuying and Li Jianrong

Analyst 2016 vol. 141(Issue 16) pp:4941-4946

Publication Date(Web):06 Jun 2016

DOI:10.1039/C6AN00626D

A sensitive and selective quantum dot (QD)-based fluorescence resonance energy transfer (FRET) biosensor was successfully fabricated for the detection of organophosphorus pesticides (OPs). 5,10,15,20-Tetra(4-pyridyl)porphyrin (TPyP) with meso-pyridyl substituents was bound to the surface of CdTe QDs to produce self-assembled nanosensors, and the process of FRET between QDs and TPyP occurred. However, the process of FRET was switched off with the addition of OPs, due to the combination between TPyP and OPs. The fluorescence intensity of TPyP (donor) would decrease gradually with the increasing concentration of OPs. Under optimal conditions, a linear correlation was established between the fluorescence intensity ratio ITPyP/IQDs and the concentration of paraoxon in the range of 9.09 × 10−12–1.09 × 10−6 mol L−1 with a detection limit of 3.15 × 10−12 mol L−1. The attractive sensitivity was obtained due to the efficient FRET and the superior fluorescence properties of QDs. The proposed method was successfully applied to the determination of the OPs in real fruit samples with satisfactory results.

Determination of ractopamine in pork using a magnetic molecularly imprinted polymer as adsorbent followed by HPLC

Co-reporter:Yiwei Tang, Jingwen Gao, Xiuying Liu, Jianxing Lan, Xue Gao, Yong Ma, Min Li, Jianrong Li

Food Chemistry 2016 Volume 201() pp:72-79

Publication Date(Web):15 June 2016

DOI:10.1016/j.foodchem.2016.01.070

•A magnetic functional monomer was prepared based on Fe3O4.•A new magnetic imprinted polymer for RAC was prepared by surface imprinting method.•A magnetic MIP-HPLC method for analysis of RAC in pork was developed.A new magnetic molecularly imprinted polymers (MMIPs) for separation and concentration of ractopamine (RAC) were prepared using surface molecular imprinting technique with methacryloyl chloride as functional monomer and RAC as template. The MMIPs were characterized using transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and vibrating sample magnetometer. The results of re-binding experiments indicated that the MMIPs had fast adsorption kinetics and could reach binding equilibrium within 20 min, and the adsorption capacity of the MMIPs was 2.87-fold higher than that of the corresponding non-imprinted polymer. The selectivity of the MMIPs was evaluated according to its recognition to RAC and its analogues. The synthesized MMIPs were successfully applied to extraction, followed by high performance liquid chromatography to determine RAC in real food samples. Spiked recoveries ranged from 73.60% to 94.5%, with relative standard deviations of <11.17%.

Highly-sensitive organophosphorus pesticide biosensors based on CdTe quantum dots and bi-enzyme immobilized eggshell membranes

Co-reporter:Gao Xue, Zhao Yue, Zhang Bing, Tang Yiwei, Liu Xiuying and Li Jianrong

Analyst 2016 vol. 141(Issue 3) pp:1105-1111

Publication Date(Web):17 Dec 2015

DOI:10.1039/C5AN02163D

An optical biosensing method using CdTe quantum dots (QDs) and bi-enzyme-immobilized eggshell membranes for the determination of organophosphorus pesticides (OPs) has been developed. Increasing amounts of OPs led to a decrease of the enzymatic activity and thus a decrease in the production of hydrogen peroxide (H2O2), which can quench the fluorescence of the CdTe QDs. Under the optimum conditions, there was a good linear relationship between the enzyme inhibition percentage and the logarithm of paraoxon or parathion concentration in the range of 1.0 × 10−11–1.0 × 10−6 mol L−1. The detection limit (S/N = 3) of the proposed biosensors were as low as 4.30 × 10−12 mol L−1 for paraoxon and 2.47 × 10−12 mol L−1 for parathion. The bi-enzyme-immobilized eggshell membrane demonstrated a long shelf-life of at least 2 months and the results showed good repeatability. The proposed method was successfully applied to the determination of the OPs in real fruit samples with satisfactory results.

Highly sensitive fluorescence detection of glycoprotein based on energy transfer between CuInS2 QDs and rhodamine B

Co-reporter:Xue Gao;Dan Li;Ying Tong;Dan Ge;Yiwei Tang;Defu Zhang ;Jianrong Li

Luminescence 2015 Volume 30( Issue 8) pp:1389-1394

Publication Date(Web):

DOI:10.1002/bio.2911

Abstract

A highly sensitive fluorescence method for glycoprotein detection has been established based on fluorescence resonance energy transfer (FRET) between CuInS₂ quantum dots (QDs) and rhodamine B (RB). Lectins comprise a group of proteins with unique affinities toward carbohydrate structures, so the process of FRET can occur between lectin-coated QDs (CuInS₂ QDs–Con A conjugates, acceptors) and carbohydrate-coated RB (RB–NH₂-glu conjugates, donors). The fluorescence of lectin-coated QDs was recovered in the presence of a glycoprotein such as glucose oxidase (GOx) and transferrin (TRF), which significantly reduced the FRET efficiency between the donor and the acceptor. Under optimal conditions, a linear correlation was established between the fluorescence intensity ratio I₆₅₄/I₅₇₇ and the TRF concentration over the range of 6.90 × 10^-10 to 3.45 × 10^-8 mol/L, with a detection limit of 2.5 × 10^-10 mol/L. The linear range for GOx is 3.35 × 10^-10 to 6.70 × 10^-8 mol/L, with a detection limit of 1.5 × 10^-10 mol/L. The proposed method was applied to the determination of glycoprotein in human serum and cell-extract samples with satisfactory results. Furthermore, CuInS₂ QDs–Con A conjugates are used as safe and efficient optical nanoprobes in HepG2 cell imaging. Copyright © 2015 John Wiley & Sons, Ltd.