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Li R.,Zhongshan Entry Exit Inspection and Quarantine Bureau | Bo Y.,Hunan Academy of Inspection and Quarantine | Bo Y.,Jinan University | Lu J.,Zhongshan Entry Exit Inspection and Quarantine Bureau | And 3 more authors.
Chinese Journal of Chromatography (Se Pu) | Year: 2016

An efficient method using gas chromatography-triple quadrupole mass spectrometry for the determination of 28 phthalate ester residues in bakery foods was established. The samples were extracted with ethyl acetate, and cleaned up with neutral alumina. The separation was performed on a TR-5MS capillary column (30 m×0.25 mm×0.25 μ m) by programmed temperature vaporization (PTV) with splitless mode. Meanwhile the identification and quantification were performed by GC-MS/MS in selected reaction monitoring (SRM) mode and using the internal standard method. The calibration curves of the 27 phthalate esters showed good linearities in the range of 0.05-10 mg/L, except diisononyl ortho-phthalate (DINP) which was in the range of 0.1-20 mg/L, with the correlation coefficients not less 0.9962. The limits of detection (LODs) were 0.1-9.8 μ g/kg and the limits of quantification (LOQs) were 0.4-32.6 μ g/kg. With the proposed method, the spiked recoveries were evaluated in four types of baked foods (bread, biscuits, cakes, stuffing) at low, medium and high concentrations. The results showed that the average recoveries of the 28 PAEs were in the range of 81.0%-117%, and the relative standard deviations (RSDs, n=6) were in the range of 1.3%-13.6%. The method was successfully applied in the investigation of the PAEs distribution in baked foods. The method is suitable for the determination of the 28 PAEs in baked foods with easy operation, high accuracy and precision.


Xu D.,Inspection and Quarantine Technology Center | Deng X.,Animal Plants and Foods Inspection and Quarantine Technical Center | Fang E.,Inspection and Quarantine Technology Center | Zheng X.,Inspection and Quarantine Technology Center | And 5 more authors.
Journal of Chromatography A | Year: 2014

A rapid and sensitive method was developed for the determination of 23 phthalates in food samples including milk-based products, distilled liquor, wine, beverage, grain, meat, oil, biscuit (cookie), and canned food by liquid chromatography tandem mass spectrometry (LC-MS/MS). Liquid samples were exacted by acetonitrile, while solid samples were prepared by QuEChERS or glass-based SPE methods. The 23 phthalates were separated on Poroshell 120 EC-C18 column and followed by positive electrospray ionization as well as multi-reaction monitoring provided by a triple-quadrupole tandem mass spectrometer. To reduce contamination, the plastic materials were avoided in sample handling and preparation The LODs were between 0.8 and 15μgkg-1 and LOQs were between 10 and 100μgkg-1. By using different concentrations: 100, 500, and 1000μgkg-1) for DINP and DIDP; 50, 100, and 1000μgkg-1 for other 21 phthalate compounds, the spiked recoveries were within 75.5-115.2% and the relative standard deviations (RSDs) were in the range of 3.2-18.9%. The proposed protocol was then applied to the analysis of 623 real samples collected from the two sides of the Taiwan Straits, and the DEHP was found in almost all samples tested in this study, with levels ranging from 0.02 to 2685mgkg-1. The present study demonstrated a rapid, sensitive, and accurate method for determining 23 phthalates in foodstuffs. © 2013 Elsevier B.V.


Guo B.,Hunan Normal University | Wang M.,Hunan Academy of Inspection and Quarantine | Liu Y.,Hunan Normal University | Zhou J.,Hunan Normal University | And 5 more authors.
Journal of Agricultural and Food Chemistry | Year: 2015

A new analytical strategy was developed that integrates a generic sample preparation into a liquid chromatography-multistage ion trap/time-of-flight mass spectrometry (LC-IT(MSn)/TOF), allowing for large-scale screening and qualitative confirmation of wide-scope illegal adulterants in different food matrices. Samples were pretreated by a fast single-tube multifunction extraction for accurate multistage mass measurement on the hybrid LC-IT/TOF system. A qualitative validation performed for over 500 analyte-matrix pairs showed the method can reduce most of the matrix effects and achieve a lower limit of confirmation at 0.1 mg/kg for 73% of the target compounds. A unique combination of dual-polarity detection, retention time, isotopic profile, and accurate MSn spectra enables more comprehensive and precise confirmation, based on the multiparameter matching by automated library searching against the user-created database. Finally, the applicability of this LC-IT(MSn)/TOF-based screening procedure for discriminating coeluting isobars, identifying nontarget adulterants, and even tentatively elucidating unexpected species in real samples is demonstrated. © 2015 American Chemical Society.


Xu D.,Xiamen Entry Exit Inspection and Quarantine Bureau | Chen Y.,Xiamen Entry Exit Inspection and Quarantine Bureau | Zhou S.,Xiamen Entry Exit Inspection and Quarantine Bureau | Lian Y.,Xiamen Entry Exit Inspection and Quarantine Bureau | And 4 more authors.
Chinese Journal of Chromatography (Se Pu) | Year: 2013

A high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/ MS) method was established for the determination of the total amount of maleic acid and maleic anhydride in starch and its products. The samples were extracted with 50% (v/v) methanol and hydrolyzed by alkaline, then analyzed by HPLC-MS/MS, and quantified with the external standard method. The mass spectrometry was operated with electrospray in negative ionization mode. The multiple reaction monitoring (MRM) mode was employed involving the transition of the precursor ion to two selected product ions, in which one pair was for quantification (m/z 115.0>71.1) and the other pair was for identification (m/z 115.0>27.1). The results indicated that no significant matrix effect was found for the spiked samples. The recoveries of maleic acid spiked in starch and its products were 80. 2%-115. 3% at spiked levels of 0.5-1 000 mg/kg. The relative standard deviations (RSDs) were less than 12% (n=6). The limits of detection (LOD) and quantification (LOQ) were 0. 1 and 0. 5 mg/kg for maleic acid and maleic anhydride, respectively. The method is rapid, sensitive and reproducible for the determination of the total amount of maleic acid and maleic anhydride in starch and its products and shows great potential for routine analysis.


Zhang F.,Central South University of forestry and Technology | Zhang F.,Changsha Environmental Protection College | Li Z.,Central South University of forestry and Technology | Zhang Y.,Hunan Academy of Inspection and Quarantine | And 2 more authors.
Chinese Journal of Chromatography (Se Pu) | Year: 2014

An analytical method based on solid-phase extraction with single-walled carbon nanotubes (SWCNTs) as adsorbent was developed for the simultaneous determination of six phthalate acid esters (PAEs) in camellia oil by gas chromatography-mass spectrometry (GC-MS). The samples were diluted by hexane and then cleaned up with a glass SWCNTs solid phase extraction (SPE) column. The PAEs were measured by GC-MS in selected ion monitoring (SIM) mode, using external standard method for quantitative analysis. The important factors affecting extraction efficiency, such as the dilution volume of hexane, the type of adsorbent material, the dosage of SWCNTs, the volume of wash solution, the type and volume of elution solution were optimized. The optimal conditions were as follows: the dilution volume of hexane was 5 mL, the dosage of SWCNTs was 0. 6 g, the wash solution was 20 mL hexane, and the elution solution was 5 mL toluene. The six PAEs had a good linear range from 0. 05 mg/L to 1. 0 mg/L, with the correlation coefficients (r) all above 0. 999 9. The average recoveries of the six targets in spiked camellia oil (from 0.05 mg/kg to 1.0 mg/kg) ranged from 86.4% to 111.7% with the relative standard deviations ( RSDs) from 4.2% to 10.4%. The developed method is accurate, quick and suitable for the determination of the six PAEs in camellia oil.


Wang Y.,Central South University | Wang Y.,Xinjiang Medical University | Huang Z.,Hunan Academy of Inspection and Quarantine | Ye Y.,Shimadzu Enterprise Management China Co. | And 2 more authors.
Chinese Journal of Chromatography (Se Pu) | Year: 2014

An analytical method for the determination of urinary cotinine of children exposed to passive smoking was established based on stable isotope dilution by gas chromatography-triple quadrupole mass spectrometry (GC-MS/MS). The samples were extracted and purified with chloroform. The extracts were determined by GC-MS/MS in multiple reaction monitoring (MRM) mode. The cotinine-d3 as an isotope internal standard was applied to quantify and confirm the urinary cotinine of children exposed to passive smoking. The method had a good linear{reversed not sign}ity from 0. 1 μg/L to 10 μg/L with the correlation coefficient (r) >0. 998. The recoveries of the cotinine in blank urine were from 79. 2% to 112. 8% at spiked levels of 0. 1, 1. 0 and 10 μg/L, with relative standard deviations (RSDs) from 2. 1% to 5. 8%. The limit of quantification (LOQ) of the method was 0. 1 μg/L. The developed method is accurate, sensitive, rapid and can be applied to detect urinary cotinine of children exposed to passive smoking at home.


Zhou W.-E.,Chinese Academy of Inspection and Quarantine | Zhou W.-E.,Guangxi University | Zhang Y.,Chinese Academy of Inspection and Quarantine | Li Y.,Guangxi University | And 7 more authors.
Journal of Chromatography A | Year: 2016

A novel, rapid and simple analytical method was developed for the quantitative determination of crocin, crocetin and geniposide in soft drink, pastry and instant noodles. The solid samples were relatively homogenized into powders and fragments. The gardenia yellow colorants were successively extracted with methanol using ultrasound-assisted extraction. The analytes were quantitatively measured in the extracts by liquid chromatography coupled with electrospray ionization tandem mass spectrometry. High correlation coefficients (r2 > 0.995) of crocin, crocetin and geniposide were obtained within their linear ranges respectively (50-1000 ng/mL, 50-1000 ng/mL, 15-240 ng/mL) by external standard method. The limits of detection (LODs) were 0.02 μg/g for crocin, 0.01 μg/g for crocetin and 0.002 μg/g for geniposide. And the limits of quantitation (LOQs) were in the ranges of 0.05-0.45 μg/g for crocin, and in the ranges of 0.042-0.32 μg/g for crocetin, and in the ranges of 0.02-0.15 μg/g for geniposide in soft drink, pastry and instant noodles samples. The average recoveries of crocin, crocetin and geniposide ranged from 81.3% to 117.6% in soft drink, pastry and instant noodles. The intra- and inter-day precisions were respectively in the range of 1.3-4.8% and 1.7-11.8% in soft drink, pastry and instant noodle. The developed methods were successfully validated and applied to the soft drink, pastry, and instant noodles collected from the located market in Beijing from China. Crocin, crocetin and geniposide were detected in the collected samples. The average concentrations ranged from 0.84 to 4.20 mg/g for crocin, and from 0.62 to 3.11 mg/g for crocetin, and from 0.18 to 0.79 mg/g for gardenia in various food samples. The method can provide evidences for government to determine gardenia yellow pigments and geniposide in food. © 2016 Elsevier B.V.


PubMed | Inspection and Quarantine Technology Center, Hunan Academy of Inspection and Quarantine and Animal Plants & Foods Inspection and Quarantine Technical Center
Type: | Journal: Journal of chromatography. A | Year: 2014

A rapid and sensitive method was developed for the determination of 23 phthalates in food samples including milk-based products, distilled liquor, wine, beverage, grain, meat, oil, biscuit (cookie), and canned food by liquid chromatography tandem mass spectrometry (LC-MS/MS). Liquid samples were exacted by acetonitrile, while solid samples were prepared by QuEChERS or glass-based SPE methods. The 23 phthalates were separated on Poroshell 120 EC-C18 column and followed by positive electrospray ionization as well as multi-reaction monitoring provided by a triple-quadrupole tandem mass spectrometer. To reduce contamination, the plastic materials were avoided in sample handling and preparation . The LODs were between 0.8 and 15 g kg(-1) and LOQs were between 10 and 100 g kg(-1). By using different concentrations: 100, 500, and 1000 g kg(-1)) for DINP and DIDP; 50, 100, and 1000 g kg(-1) for other 21 phthalate compounds, the spiked recoveries were within 75.5-115.2% and the relative standard deviations (RSDs) were in the range of 3.2-18.9%. The proposed protocol was then applied to the analysis of 623 real samples collected from the two sides of the Taiwan Straits, and the DEHP was found in almost all samples tested in this study, with levels ranging from 0.02 to 2685 mg kg(-1). The present study demonstrated a rapid, sensitive, and accurate method for determining 23 phthalates in foodstuffs.


PubMed | Hunan Academy of Inspection and Quarantine, Chinese Academy of Inspection and Quarantine and Guangxi University
Type: | Journal: Journal of chromatography. A | Year: 2016

A novel, rapid and simple analytical method was developed for the quantitative determination of crocin, crocetin and geniposide in soft drink, pastry and instant noodles. The solid samples were relatively homogenized into powders and fragments. The gardenia yellow colorants were successively extracted with methanol using ultrasound-assisted extraction. The analytes were quantitatively measured in the extracts by liquid chromatography coupled with electrospray ionization tandem mass spectrometry. High correlation coefficients (r(2)>0.995) of crocin, crocetin and geniposide were obtained within their linear ranges respectively (50-1000ng/mL, 50-1000ng/mL, 15-240ng/mL) by external standard method. The limits of detection (LODs) were 0.02g/g for crocin, 0.01g/g for crocetin and 0.002g/g for geniposide. And the limits of quantitation (LOQs) were in the ranges of 0.05-0.45g/g for crocin, and in the ranges of 0.042-0.32g/g for crocetin, and in the ranges of 0.02-0.15g/g for geniposide in soft drink, pastry and instant noodles samples. The average recoveries of crocin, crocetin and geniposide ranged from 81.3% to 117.6% in soft drink, pastry and instant noodles. The intra- and inter-day precisions were respectively in the range of 1.3-4.8% and 1.7-11.8% in soft drink, pastry and instant noodle. The developed methods were successfully validated and applied to the soft drink, pastry, and instant noodles collected from the located market in Beijing from China. Crocin, crocetin and geniposide were detected in the collected samples. The average concentrations ranged from 0.84 to 4.20mg/g for crocin, and from 0.62 to 3.11mg/g for crocetin, and from 0.18 to 0.79mg/g for gardenia in various food samples. The method can provide evidences for government to determine gardenia yellow pigments and geniposide in food.


PubMed | Hunan Academy of Inspection and Quarantine and Central South University
Type: Journal Article | Journal: Acta paediatrica (Oslo, Norway : 1992) | Year: 2016

This study aimed to test the association between fathers smoking behaviour and urinary cotinine levels among preschool children exposed to environmental tobacco smoke (ETS). Possible factors influencing this association were also explored.We recruited 368 smoking fathers with children aged five to six from five preschools in the city of Changsha, China. Urine samples were collected from the children, and the fathers were interviewed face-to-face. We adjusted for potential confounding factors with linear regression models.The geometric mean of the cotinine concentration in the childrens urine was 3.94ng/mL (95% confidence interval 3.71-4.22). In multivariate analyses, the important predictors of urinary cotinine levels among children, after adjusted confounding factors, were the number of cigarettes smoked in front of the children at home per day (B=0.414, p<0.001), the number of cigarettes smoked by the father in front of the children at home (B=0.105, p<0.001) and the mean duration of the childrens exposure to ETS at home (B=0.111; p=0.046).Urinary cotinine concentrations of children exposed to ETS at home were positively associated with smoking fathers and smoking behaviours and the mean duration of ETS exposure at home. Targeted interventions are urgently needed to reduce childrens exposure.

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