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Zhang W.,Zhangzhou Normal University | Su Y.,Zhangzhou Normal University | Shi J.,Zhangzhou Normal University | Zhang M.,Zhangzhou Normal University | And 7 more authors.
Analytical Methods | Year: 2014

In this paper, a high performance liquid chromatography technique is established for quantification of paraquat in blood. Samples were pretreated by mixing with hydrochloric acid for precipitation of protein, followed by acetonitrile extraction, ultrasonication, centrifugation, and filtration. In addition, with sodium heptane-acetonitrile-water (1.82 g/50 mL/450 mL) buffer solution as the mobile phase and a C18 column as the stationary phase, liquid chromatography separation and determination was carried out on samples of paraquat using a variable wavelength UV detector. The linear range was 0.3-30 μg mL-1 (R = 0.9999) with a minimum detection limit for paraquat of 0.026 μg mL-1 (S/N ≧ 3), and limit of quantification of 0.08 μg mL-1. Moreover, the method proposed here is sensitive and accurate, and should have a bright future in numerous practical applications. This journal is © the Partner Organisations 2014. Source

Li S.,Zhangzhou Normal University | Li S.,Fujian Provincial Key Laboratory of Modern Analytical Science and Separation Technology | Zheng J.,Zhangzhou Normal University | Zheng J.,CAS National Center for Nanoscience and Technology | And 8 more authors.
Nanoscale | Year: 2013

A facile and effective way for the preparation of nano-sized Fe 3O4@graphene yolk-shell nanoparticles via a hydrothermal method is developed. Moreover, the targeting properties of the materials for anticancer drug (doxorubicin hydrochloride) delivery are investigated. Excitingly, these hybrid materials possess favorable dispersibility, good superparamagnetism (the magnetic saturation value is 45.740 emu g-1), high saturated loading capacity (2.65 mg mg-1), and effective loading (88.3%). More importantly, the composites exhibit strong pH-triggered drug release response (at the pH value of 5.6 and 7.4, the release rate was 24.86% and 10.28%, respectively) and good biocompatibility over a broad concentration range of 0.25-100 μg mL-1 (the cell viability was 98.52% even at a high concentration of 100 μg mL-1) which sheds light on their potentially bright future for bio-related applications. © 2013 The Royal Society of Chemistry. Source

Wu W.,Zhangzhou Normal University | Wu W.,Fujian Provincial Key Laboratory of Modern Analytical Science and Separation Technology | Lin Y.,Zhangzhou Normal University | Chen J.,Zhangzhou Normal University | Chen J.,Fujian Provincial Key Laboratory of Modern Analytical Science and Separation Technology
Chinese Journal of Environmental Engineering | Year: 2014

The surface of molecular sieve 4A was modified with cationic surfactant by using impregnation method, and the adsorption of Cr(VI) on modified molecular sieve 4A was improved by forming the anion exchange membrane between quaternary ammonium cation and bromide anion. The phase structures and composition of the samples were characterized by the X-ray diffraction(XRD) and the Fourier transform infrared spectroscopy(FTIR). The study shows that the adsorption of modified molecular sieve 4A is affected by surfactant nature and chain structure of hydrophobic group, and the octadecy trimethyl ammonium bromide (OTAB) modified molecular sieve 4A with longer hydrophobic chain are provided with more dense bilayers and more adsorption capacities of dichromate anion. The Cr(VI) adsorption data were analyzed using pseudo-first-order, pseudo-sencond-order and Elovich as well as Bangham kinetic model, the pseudo-first-order was the most appropriate equation to predict the sorption behaviour of OTAB-modified molecular sieve 4A. The Cr(VI) uptake was also quantitatively evaluated using Langmuir, Freundlich, Redlich-Peterson, and Tempkin isotherm models, Cr(VI) sorption capacity of 13.98 mg/g and the uniform adsorption playing a dominant role were derived from Langmuir and Redlich-Peterson isotherm. Source

Cao X.,Zhangzhou Normal University | Cao X.,Fujian Provincial Key Laboratory of Modern Analytical Science and Separation Technology | Ma J.,Zhangzhou Normal University | Ma J.,Fujian Provincial Key Laboratory of Modern Analytical Science and Separation Technology | And 9 more authors.
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2015

A facile microwave-assisted solvothermal method was used to prepare fluorescent carbon nitride quantum dots (CNQDs) using oleic acid as the reaction media at moderate reaction temperature in a short time (5 min). Citric acid monohydrate and urea were used as the precursors. The as-prepared CNQDs were characterized by multiple analytical techniques. The CNQDs exhibited an uncommon excitation wavelength-dependent fluorescence with two maximum emission peaks at 450 and 540 nm. The CNQDs with a quantum yield of 27.1% could serve as an effective fluorescent sensing platform for label-free sensitive detection of Hg2+ ions with a detection limit of 0.14 μM. This method was also applied to the detection of Hg2+ ions in tap water samples. © 2015 Elsevier B.V. All rights reserved. Source

Lin Y.,Zhangzhou Normal University | Lin Y.,Fujian Provincial Key Laboratory of Modern Analytical Science and Separation Technology | Yao B.,Zhangzhou Normal University | Yao B.,Fujian Provincial Key Laboratory of Modern Analytical Science and Separation Technology | And 8 more authors.
Microchimica Acta | Year: 2016

The authors report that nitrogen-doped carbon dots (N-CDs) represent a viable fluorescent probe for the determination of dissolved free chlorine. The N-CDs can be fairly easily prepared by a solvothermal method using citric acid, tartaric acid and ethanediamine as the precursors, display excitation/emission maxima of 360/460 nm, and have a quantum yield of 42.2 %. Free chlorine and ClO− quench fluorescence, and this was exploited to design a method for fluorometric determination of chlorine and hypochlorite. The probe has a short response time (< 1 min), excellent selectivity, high sensitivity, and a linear response range that extends from 0.1 to 27 μM. The limit of detection is as low as 29.7 nM. The method was applied to the determination of chlorine dissolved in tap water. [Figure not available: see fulltext.] © 2016 Springer-Verlag Wien Source

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