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Cai M.-Q.,Zhejiang GongShang University | Wei X.-Q.,Zhejiang GongShang University | Du C.-H.,Zhejiang GongShang University | Ma X.-M.,Zhejiang GongShang University | And 2 more authors.
Journal of Chromatography A | Year: 2014

A novel amphiphilic polymeric ionic liquid membrane containing a hydrophilic bromide anion and a hydrophobic carbonyl group was synthesized in dimethylformamide (DMF) systems using the ionic liquid 1-butyl-3-vinylimidazolium bromide (BVImBr) and the methylmethacrylate (MMA) as monomers. The prepared amphiphilic ploy-methylmethacrylate-1-butyl-3-vinylimidazolium bromide (MMA-BVImBr) was characterized by a scanning electron microscope and an infrared spectrum instrument. The results of solid-phase micro-extraction membrane (SPMM) experiments showed that the adsorption capacity of membrane was about 0.76μgμg-1 for aniline. Based on this, a sensitive method for the determination of trace aniline, as a degradation product of azo dye Orange G under sonication, was developed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The calibration curve showed a good linearity ranging from 0.5 to 10.0μgL-1 with a correlation coefficient value of 0.9998. The limit of quantification was 0.5μgL-1. The recoveries ranged from 90.6% to 96.1%. The intra- and inter-day relative standard deviations were less than 8.3% and 10.9%. The developed SPMM-LC-MS/MS method was used successfully for preconcentration of trace aniline produced during the sonication of Orange G solution. © 2014 Elsevier B.V..


Zhao Y.-G.,Centers for Disease Control and Prevention | Zhao Y.-G.,Ningbo Key Laboratory of Poison Research and Control | Zhou L.-X.,Ningbo University | Pan S.-D.,Centers for Disease Control and Prevention | And 6 more authors.
Journal of Chromatography A | Year: 2014

A novel, simple and sensitive method was developed for the simultaneous determination of 22 sulfonamides (SAs) in chicken breast muscle by using the dispersive micro-solid-phase extraction (d- μ-SPE) procedure combined with ultra-fast liquid chromatography-tandem quadrupole mass spectrometry (UFLC-MS/MS). The excellent core-shell nanoring amino-functionalized superparamagnetic molecularly imprinted polymer (CS-NR-Mag-MIP) was used as sorbent, and the main factors affecting the extraction efficiency were investigated in detail. All target compounds showed good linearities in the tested range with correlation coefficients (r) higher than 0.9980. The mean recoveries were in the range of 85.0-112.2% at low, medium and high concentration levels (0.1, 1.0 and 5.0. ng/g). The intra-day and inter-day relative standard deviations (RSDs) were lower than 6.0% and 8.9%, respectively. The limits of quantification for the 22 SAs were between 0.013 and 0.099. ng/g. The developed d- μ-SPE-UFLC-MS/MS method had been successfully applied to the chicken breast muscle samples for food-safety risk monitoring in Zhejiang Province, China. The results showed sulfamethazine, sulfamethoxazole and sulfaquinoxaline in five out of three hundred collected samples were detected with concentrations of 0.418-2.28, 16.4 and 2.93. ng/g, respectively. It was confirmed that the CS-NR-Mag-MIP was a kind of highly effective d- μ-SPE materials used for the SAs analyses. © 2014 Elsevier B.V.


Cai M.Q.,Zhejiang GongShang University | Cai M.Q.,Centers for Disease Control and Prevention | Wei X.Q.,Zhejiang GongShang University | Song Z.J.,Zhejiang GongShang University | And 2 more authors.
Ultrasonics Sonochemistry | Year: 2015

In this work, the decolorization of azo dye Orange G (OG) in aqueous solution by aluminum powder enhanced by ultrasonic irradiation (AlP-UI) was investigated. The effects of various operating operational parameters such as the initial pH, initial OG concentration, AlP dosage, ultrasound power and added hydrogen peroxide (H2O2) concentration were studied. The results showed that the decolorization rate was enhanced when the aqueous OG was irradiated simultaneously by ultrasound in the AlP-acid systems. The decolorization rate decreased with the increase of both initial pH values of 2.0-4.0 and OG initial concentrations of 10-80 mg/L, increased with the ultrasound power enhancing from 500 to 900 W. An optimum value was reached at 2.0 g/L of the AlP dosage in the range of 0.5-2.5 g/L. The decolorization rate enhanced significantly by the addition of hydrogen peroxide in the range of 10-100 mM to AlP-UI system reached an optimum value of 0.1491 min-1. The decolorization of OG appears to involve primarily oxidative steps, the cleavage of NN bond, which were verificated by the intermediate products of OG under the optimal tested degradation system, aniline and 1-amino-2-naphthol-6,8- disulfonate detected by the LC-MS. © 2014 Elsevier B.V. All rights reserved.


Cai M.,Zhejiang GongShang University | Jin M.,Ningbo Key Laboratory of Poison Research and Control | Weavers L.K.,Ohio State University
Ultrasonics Sonochemistry | Year: 2011

In this paper, seven new sonolytic degradation products of Orange G were found and identified using powerful analytical techniques such as liquid chromatography-electrospray ionization mass spectrometry (LC-ESI-MS), tandem mass spectrometry (MS/MS), and liquid chromatography with diode-array detection (LC-DAD). Each technique provided complementary information for the degradation products identification. In order to resolve the MS and MS/MS spectra obtained, the separation conditions were optimized. Among them, Orange G was unambiguously identified based on its abundant [M-H] - ion, [M + H] + ion, ultra-violet and visible spectra, retention time, and tandem mass spectrometric analysis compared with an authentic standard. The seven new degradation products were tentatively identified based on ultra-violet and visible spectra, [M-H] - ions, and tandem mass spectrometry. The neutral losses of SO 2, SO 3, N 2 and H 2O for MS/MS spectra which appear to be characteristic of the negative ion mode were observed. Based on this by-product identification, a possible multi-step degradation scheme is proposed. The analysis results of degradation products reveal that the degradation mechanism proceeds via reductive cleavage of the azo linkage, as well as intermolecular dehydration and desulfonation due to the powerful oxidizing hydroxyl radicals as well as hydrogen radical. © 2011 Elsevier B.V. All rights reserved.


Zhao Y.-G.,Ningbo Key Laboratory of Poison Research and Control | Chen X.-H.,Ningbo Key Laboratory of Poison Research and Control | Chen X.-H.,Ningbo University | Pan S.-D.,Ningbo Key Laboratory of Poison Research and Control | And 4 more authors.
Journal of Materials Chemistry A | Year: 2013

A novel core-shell nanoring amino-functionalized magnetic molecularly imprinted polymer (CS-NR-Mag-MIP) was synthesized by ultrasound-assisted suspension polymerization. CS-NR-Mag-MIP nanoparticles showed higher adsorption capacity, more specific selectivity, and faster binding ability than core-shell nanosphere amino-functionalized magnetic molecularly imprinted polymer (CS-NS-Mag-MIP) nanoparticles prepared by conventional mechanical agitation (CMA). The results indicate that CS-NR-Mag-MIP nanoparticles have promising potential for BPA enrichment and removal during water treatment operations. © 2013 The Royal Society of Chemistry.


Chen X.-H.,Ningbo Key Laboratory of Poison Research and Control | Chen X.-H.,Ningbo University | Zhao Y.-G.,Ningbo Key Laboratory of Poison Research and Control | Shen H.-Y.,Zhejiang University | And 2 more authors.
Journal of Chromatography A | Year: 2012

A novel and effective dispersive solid-phase extraction (dSPE) procedure with rapid magnetic separation using ethylenediamine-functionalized magnetic polymer as an adsorbent was developed. The new procedure had excellent clean-up ability for the selective removal of the matrix in red wine. An accurate, simple, and rapid analytical method using ultra-fast liquid chromatography-tandem quadrupole mass spectrometry (UFLC-MS/MS) for the simultaneous determination of nine food additives (i.e., acesulfame, saccharin, sodium cyclamate, aspartame, benzoic acid, sorbic acid, stevioside, dehydroacetic acid, and neotame) in red wine was also used and validated. Recoveries ranging from 78.5% to 99.2% with relative standard deviations ranging from 0.46% to 6.3% were obtained using the new method. All target compounds showed good linearities in the tested range with correlation coefficients (r) higher than 0.9993. The limits of quantification for the nine food additives were between 0.10 μg/L and 50.0 μg/L. The proposed dSPE-UFLC-MS/MS method was successfully applied in the food-safety risk monitoring of real red wine in Zhejiang Province, China. © 2012.


Zhao Y.-G.,Ningbo Key Laboratory of Poison Research and Control | Chen X.-H.,Ningbo Key Laboratory of Poison Research and Control | Chen X.-H.,Ningbo University | Pan S.-D.,Ningbo Key Laboratory of Poison Research and Control | And 4 more authors.
Talanta | Year: 2013

A novel, simple and sensitive method was developed for the simultaneous determination of eight phenolic environmental estrogens in blood by using the dispersive micro-solid-phase extraction (d-μ-SPE) procedure combined with ultra-fast liquid chromatography-tandem quadrupole mass spectrometry (UFLC-MS/MS). The excellent nanomaterials tetraethylenepentamine-functionalized magnetic polymer was used as an adsorbent, and the main factors affecting the extraction efficiency were investigated in detail. All target compounds showed good linearities in the tested range with correlation coefficients (r) higher than 0.999. The mean recoveries were in the range of 85.0-105.0%. The intra-day and inter-day relative standard deviations (RSDs) were lower than 4.9% and 5.2%, respectively. The limits of quantification for the eight phenolic environmental estrogens were between 0.075 and 0.42 μg L-1. The developed method can be applied to the routine analyses for the determination of the eight phenolic environmental estrogens in blood samples. © 2013 The Authors.


Yao X.-P.,Ningbo Key Laboratory of Poison Research and Control | Fu Z.-J.,Linzhou Institute for Food and Drug Control | Zhao Y.-G.,Ningbo Key Laboratory of Poison Research and Control | Wang L.,Ningbo Key Laboratory of Poison Research and Control | And 2 more authors.
Talanta | Year: 2012

A new method that utilizes tetraethylenepentamine-functional Fe 3O 4 magnetic polymers (TEPA-NMPs) as a solid-phase extractant for matrix solid phase dispersion extraction (MSPD) has been developed for preconcentration of Cr(VI) at ultratrace levels prior to the measurement by flame atomic absorption spectroscopy (FAAS). The separation/preconcentration conditions of Cr(VI) was investigated, including the pH value, shaking time, adsorption temperature, sample volume, desorption conditions and interfering ions. The results showed the adsorption properties of the TEPA-NMPs were highly pH dependent. The data of adsorption kinetics obeyed pseudo-second-order rate mechanism well. Adsorption thermodynamic studies suggested that the adsorption processes of Cr(VI) onto the TEPA-NMPs was endothermic and entropy favored in nature. Under the best experimental conditions, the enhancement factor was 125 times, the detection limit of the method was 0.16 μg L -1 and the relative standard deviation was 1.9% (n=7). Furthermore, the developed method was validated by comparing with Graphite Furnace atomic absorption spectrometry (GF-AAS) method, and has been applied for the determination of ultratrace Cr(VI) ions in the river and tap water samples with satisfactory results, which revealed the sensitivity of the proposed TEPA-NMPs MSPD-FAAS method was comparable with that of GF-AAS method. © 2012 Elsevier B.V. All rights reserved.


Shi J.,Ningbo Key Laboratory of Poison Research and Control
Se pu = Chinese journal of chromatography / Zhongguo hua xue hui | Year: 2010

A method for the simultaneous analysis of 43 pesticide residues in vegetables by gas chromatography coupled with triple quadrupole mass spectrometry (GC-QqQ-MS/MS) was developed and validated. The samples were extracted with acetonitrile, and then purified by solid-phase extraction (SPE). The detection of 43 pesticides was carried out by GC-QqQ-MS/MS in the multi-reaction monitoring (MRM) mode using external standard method. The overall recoveries determined at three spiked levels of 10, 80 and 100 microg/kg were 62.2%-170.0%, which in the recoveries of 36 pesticides were 70.0%-120.0%. The relative standard deviations (RSDs) were less than 18%. The limits of quantification (S/N > or =10) were 0.3-4.4 microg/kg. The method possesses low background and high sensitivity. It can be applied to the routine analysis of the 43 pesticides in vegetables.


Zhao Y.-G.,Ningbo Key Laboratory of Poison Research and Control | Shen H.-Y.,Zhejiang University | Shi J.-W.,Ningbo Key Laboratory of Poison Research and Control | Chen X.-H.,Ningbo Key Laboratory of Poison Research and Control | Jin M.-C.,Ningbo Key Laboratory of Poison Research and Control
Journal of Chromatography A | Year: 2011

In this paper, a novel and recyclable amino-functionalized nano-composite material (NCM) using tetraethylenepentamine (TEPA) as a coupling agent was synthesized. The properties of the TEPA-NCM were characterized by transmission electron microscopy (TEM), Fourier transform infrared analysis (FTIR), thermogravimetric analysis (TGA) and elemental analysis (EA). An effective dispersive solid-phase extraction (dSPE) procedure using the TEPA-NCM was developed, and comparative studies were carried out among Carbon/NH2 SPE, primary secondary amine (PSA) dSPE and TEPA-NCM dSPE. The results showed that TEPA-NCM dSPE was faster, easier and more effective to clean and enrich than the Carbon/NH2 cartridges, and the TEPA-NCM was much more effective to remove the pigments in vegetable samples than the PSA materials. The TEPA-NCM could be reused at least five times without much sacrifice of the cleanup efficiency. Furthermore, a gas chromatography-triple quadrupole mass spectrometry (GC-QqQ-MS/MS) method was established for the simultaneous determination of 29 pesticides (such as organochlorine and organophosphorus pesticides) in vegetables by dSPE using acetonitrile as an extraction solvent and TEPA-NCM as an adsorbent instead of PSA. The recoveries were in the range of 75-114% for all analytes except for trans-chlordane. The RSDs were in the range of 2-17%. The linearities were in the range of 0.4-100.0μg/kg with determination coefficients (r2) higher than 0.986 for all compounds. The limits of detection (LODs) for all pesticides were less than 0.29μg/kg and the limits of quantification (LOQs) were between 0.17 and 0.95μg/kg. The developed method was applied to fifteen real vegetable samples, and it was confirmed that the TEPA-NCM was one of a kind of highly effective dSPE materials used for the pesticides analyses. © 2011 Elsevier B.V.

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