Wang-Hsien Ding

National Central University, Taoyuan City, Taiwan, Taiwan

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Publications (52)181.01 Total impact

  • Hsin-Chang Chen, Han-Wen Kuo, Wang-Hsien Ding
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    ABSTRACT: An optimized method for the determination of two major carbon-based engineered nanoparticles (C60 and C70) in marketed fish samples is described. The method involves the use of microwave-assisted extraction (MAE) coupled with liquid chromatography - tandem mass spectrometry with atmospheric pressure photoionization (LC-APPI-MS/MS). Factors affecting the extraction efficiency of the analytes from fish samples were optimized by a central composite design method. The optimal extraction temperature and time for MAE were found to be 233 °C for 22 min, and the extraction solution was composed of toluene and acetone in a ratio of 4.64:1. The limits of quantitation (LOQs) were 0.1 and 0.05 ng/g for C60 and C70, respectively. The precision for these analytes at two spiked levels, as indicated by relative standard deviations (RSDs), were less than 10% for both intra- and inter-day analysis. Accuracy, expressed as the mean extraction recovery, was between 85 and 98%. The method was further validated based on EU Commission Decision 2002/657/EC, including a decision limit (CCα) and detection capability (CCβ) for marketed fish samples.
    Journal of the Chinese Chemical Society. 01/2014;
  • Chien-Liang Chen, Dung-Ying Tsai, Wang-Hsien Ding
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    ABSTRACT: A method for the determination of chlorinated flame retardants: Dechlorane Plus, Dechlorane (Dec) 602, Dec 603 and Dec 604, in marketed fish is described. The method involves the use of matrix solid-phase dispersion (MSPD) prior to their determination by gas chromatography–electron-capture negative-ion chemical-ionisation mass spectrometry (GC–ECNICI-MS). Parameters that affect the extraction efficiency of the target analytes from fish samples were optimised using a Box–Behnken design method. MSPD integrated the extraction and clean-up procedures into a single step, which provides the benefits of being simple and convenient. The optimal extraction conditions involved dispersing a freeze-dried fish (1-g) in 2-g of silica gel, and packed with 1-g of Florisil, and then the target analytes were eluted with 20 mL of n-hexane. The limits of quantification were 9–15 pg/g-lipid weight. Preliminary results showed that the total concentrations of the target analytes ranged from 0.15 to 1.3 ng/g-lipid weight.
    Food Chemistry. 01/2014; 164:286–292.
  • Dung-Ying Tsai, Chien-Liang Chen, Wang-Hsien Ding
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    ABSTRACT: A simple and effective method for the rapid determination of five salicylate and benzophenone-type UV absorbing substances in marketed fish is described. The method involves the use of matrix solid-phase dispersion (MSPD) prior to their determination by on-line silylation gas chromatography tandem mass spectrometry (GC–MS/MS). The parameters that affect the extraction efficiency were optimized using a Box–Behnken design method. The optimal extraction conditions involved dispersing 0.5 g of freeze-dried powdered fish with 1.0 g of Florisil using a mortar and pestle. This blend was then transferred to a solid-phase extraction (SPE) cartridge containing 1.0 g of octadecyl bonded silica (C18), as the clean-up co-sorbent. The target analytes were then eluted with 7 mL of acetonitrile. The extract was derivatized on-line in the GC injection-port by reaction with a trimethylsilylating (TMS) reagent. The TMS-derivatives were then identified and quantitated by GC–MS/MS. The limits of quantitation (LOQs) were less than 0.1 ng/g.
    Food Chemistry 01/2014; 154:211–216. · 3.33 Impact Factor
  • Wu-Hsun Chung, Shin-Hwa Tzing, Wang-Hsien Ding
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    ABSTRACT: A simple and solvent-free method for the rapid analysis of five synthetic polycyclic musks in water samples is described. The method involves the use of dispersive micro solid-phase extraction (D-μ-SPE) coupled with direct thermal desorption (TD) gas chromatography-mass spectrometry (GC-MS) operating in the selected-ion-storage (SIS) mode. The parameters affecting the extraction efficiency of the target analytes from water sample and the thermal desorption conditions in the GC injection-port were optimized using a central composite design method. The optimal extraction conditions involved immersing 3.2mg of a typical octadecyl (C18) bonded silica adsorbent (i.e., ENVI-18) in a 10mL water sample. After extraction by vigorously shaking for 1.0min, the adsorbents were collected and dried on a filter. The adsorbents were transferred to a micro-vial, which was directly inserted into GC temperature-programmed injector, and the extracted target analytes were then thermally desorbed in the GC injection-port at 337°C for 3.8min. The limits of quantitation (LOQs) were determined to be 1.2-3.0ng/L. Precision, as indicated by relative standard deviations (RSDs), was less than 9% for both intra- and inter-day analysis. Accuracy, expressed as the mean extraction recovery, was between 74 and 90%. A preliminary analysis of the river water samples revealed that galaxolide (HHCB) and tonalide (AHTN) were the two most common synthetic polycyclic musks present. Using a standard addition method, their concentrations were determined to in the range from 11 to 140ng/L.
    Journal of Chromatography A 07/2013; · 4.61 Impact Factor
  • Jen-Wen Wu, Hsin-Chang Chen, Wang-Hsien Ding
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    ABSTRACT: A rapid procedure, using minimal amounts of solvent, for the reliable determination of five salicylate and benzophenone-type ultraviolet (UV) filters: ethylhexyl salicylate (EHS), 3,3,5-trimethyl-cyclohexyl salicylate (HMS), 2-hydroxy-4-methoxybenzophenone (BP-3), 2,4-dihydroxy-benzophenone (BP-1) and 2,2'-dihydroxy-4-methoxybenzophenone (BP-8), in aqueous samples is described. The method involves an ultrasound-assisted dispersive liquid-liquid microextraction (UA-DLLME) plus simultaneous silylation prior to their determination by gas chromatography-mass spectrometry (GC-MS). The parameters affecting the extraction and derivatization efficiency of the target UV filters from aqueous samples were systematically investigated and the conditions optimized. The optimal silylation and extraction conditions involved the rapid injection of a mixture of 750μL of acetone (as a dispersant), 15μL of tetrachloroethylene (as an extractant), and 20μL of BSTFA (as a derivatizing agent) into a 10-mL volume of aqueous samples (pH 7.0) containing 0.5g of sodium chloride in a glass tube with a conical bottom. After ultrasonication for 2.0min and centrifugation at 5000rpm (10min), the sedimented phase 5.0μL was directly introduced into the GC-MS. The limits of quantitation (LOQs) were less than 6ng/L. The precision for these analytes, as indicated by the relative standard deviations (RSDs), was less than 9% for both intra- and inter-day analysis. Accuracy, expressed as the mean extraction recovery, was between 74 and 92%. The method was then applied to environmental aqueous samples, using a standard addition method, showing the occurrence of BP-3 in samples of both river water and municipal wastewater treatment plant (MWTP) effluents.
    Journal of Chromatography A 06/2013; · 4.61 Impact Factor
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    ABSTRACT: A sensitive procedure, microwave-assisted extraction (MAE) coupled dispersive micro solid-phase extraction (D-μ-SPE), was developed to extract N-nitrosodimethylamine (NDMA) and other six volatile N-nitrosamines (NAms) from meat products. Parameters affecting the efficiency of MAE and D-μ-SPE were systematically investigated. For MAE, 5-g of a homogenised meat sample was extracted with 30mL of a sodium hydroxide (0.025M) solution at 100°C for 10min. The optimum D-μ-SPE conditions were immersing 100mg of Carboxen™ 1000 adsorbent in the MAE extract. After vigorously shaking for 30min, the NAms were then desorbed by treatment with 200μL of dichloromethane. A 10μL aliquot was determined by gas chromatography with chemical ionisation mass spectrometry (GC-CI-MS) using the selected-ion-storage (SIS) mode. The limits of quantitation (LOQs) were 0.03-0.36ng/g. Preliminary results revealed that NDMA was present in the highest concentration, ranging from 0.8 to 3.2ng/g.
    Food Chemistry 05/2013; 138(1):227-33. · 3.33 Impact Factor
  • Yu-Pei Wu, Yu-Chen Wang, Wang-Hsien Ding
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    ABSTRACT: A rapid and solvent-free procedure for the determination of 4-tert-octylphenol and 4-nonylphenol isomers in aqueous samples is described. The method involves in-situ acetylation and microwave-assisted headspace solid-phase microextraction prior to their determination using gas chromatography-ion trap mass spectrometry operated in the selected ion storage mode. The dual experimental protocols to evaluate the effects of various derivatization and extraction parameters were investigated and the conditions optimized. Under optimized conditions, 300 μL of acetic anhydride mixed with 1 g of potassium hydrogencarbonate and 2 g of sodium chloride in a 20 mL aqueous sample were efficiently extracted by a 65 μm polydimethylsiloxane-divinylbenzene fiber that was located in the headspace when the system was microwave irradiated at 80 W for 5 min. The limits of quantitation were 5 and 50 ng/L for 4-tert-octylphenol and 4-nonylphenol isomers, respectively. The precision for these analytes, as indicated by relative standard deviations, were less than 8% for both intra- and inter-day analysis. Accuracy, expressed as the mean extraction recovery, was between 74 to 88%. A standard addition method was used to quantitate 4-tert-octylphenol and 4-nonylphenol isomers, and the concentrations ranged from 120 to 930 ng/L in various environmental water samples.
    Journal of Separation Science 08/2012; 35(16):2122-30. · 2.59 Impact Factor
  • Source
    Shin-Fang Wu, Li-Lian Liu, Wang-Hsien Ding
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    ABSTRACT: A rapid, simple and solvent-free procedure was developed for the determination of synthetic polycyclic musks in oyster samples by using one-step microwave-assisted headspace solid-phase microextraction (MA-HS-SPME) and gas chromatography–mass spectrometry (GC–MS). Two commonly used synthetic polycyclic musks, galaxolide (HHCB) and tonalide (AHTN), were selected in the method development and validation. The parameters (microwave irradiation power, extraction time, amount of water added, pH value and addition of NaCl) affecting the extraction efficiency of analytes from oyster slurry were systematically investigated and optimised. The best extraction conditions were achieved when the oyster tissue mixed with 10-mL deionised water (containing 3 g of NaCl in a 40-mL sample-vial) was microwave irradiated at 80 W for 5 min. The limit of quantification (LOQ) was 0.1 ng/g in 5-g of wet tissue. The good precision and accuracy of one-step MA-HS-SPME coupled with GC–MS for the determination of trace level of AHTN in oyster samples was also demonstrated.
    Food Chemistry. 07/2012; 133(2):513–517.
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    ABSTRACT: A simple sample pretreatment technique, dispersive micro-solid phase extraction, was applied for the extraction of N-nitrosodimethylamine (NDMA) and other four N-nitrosamines (NAs) from samples of swimming pool water. The parameters affecting the extraction efficiency were systematically investigated. The best extraction conditions involved immersing 75 mg of carbon molecular sieve, Carboxen™ 1003 (as an adsorbent), in a 50-mL water sample (pH 7.0) containing 5% sodium chloride in a sample tube. After 20 min of extraction by vigorous shaking, the adsorbent was collected on a filter and the NAs desorbed by treatment with 150 μL of dichloromethane. A 10-μL aliquot was then directly determined by large-volume injection gas chromatography with chemical ionization mass spectrometry using the selected ion storage mode. The limits of quantitation were <0.9 ng/L. The precision for these analytes, as indicated by relative standard deviations, were <8% for both intra- and inter-day analyses. Accuracy, expressed as the mean extraction recovery, was between 62% and 109%. A preliminary analysis of swimming pool water samples revealed that NDMA was present in the highest concentration, in the range from n.d. to 100 ng/L.
    Analytical and Bioanalytical Chemistry 02/2012; 402(6):2209-16. · 3.66 Impact Factor
  • Hsin-Chang Chen, Wang-Hsien Ding
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    ABSTRACT: A simple and solvent-minimized method for the determination of three aqueous fullerene aggregates (nC₆₀, nC₇₀, and aqueous [6,6]-phenyl C₆₁ butyric acid methyl ester (nPCBM)) in water samples is described. The method involves the use of ultrasound-assisted dispersive liquid-liquid microextraction (UA-DLLME) coupled liquid chromatography-tandem mass spectrometry with atmospheric pressure photoionization (LC-APPI-MS/MS). The parameters affecting the extraction efficiency of the analytes from water samples were systematically investigated and the conditions optimized. The best extraction conditions involved the rapid injection of a mixture of 1.0 mL of 2-propanol (as a disperser solvent) and 10 μL of benzyl bromide (as an extraction solvent) into 10 mL of an aqueous solution (pH 10.0) containing 1% sodium chloride in a conical bottom glass tube. After ultrasonication for 1.0 min and centrifugation at 5000 pm (10 min), the sedimented phase 5.0 μL was directly injected into the LC-APPI-MS/MS system. The limits of quantification (LOQs) were 150, 60 and 8 ng L⁻¹ for nPCBM, nC₆₀ and nC₇₀, respectively. The precision for these analytes, as indicated by relative standard deviations (RSDs), were less than 12% for both intra- and inter-day analysis. Accuracy, expressed as the mean extraction recovery, was between 70 and 86%. A standard addition method was used to quantitate three aqueous fullerene aggregates, and the concentrations of these aqueous fullerene aggregates were determined to be in the range from n.d. to 130 ng L⁻¹ in various environmental samples including municipal influent and effluent samples, industrial wastewater samples, and surface water samples.
    Journal of Chromatography A 12/2011; 1223:15-23. · 4.61 Impact Factor
  • Ching-Ya Yang, Wang-Hsien Ding
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    ABSTRACT: A simple and solvent-minimized procedure for the determination of six commonly found synthetic polycyclic musks in aqueous samples using ultrasound-assisted dispersive liquid-liquid microextraction (UA-DLLME) coupled with gas chromatography-mass spectrometry (GC-MS) is described. The parameters affecting the extraction efficiency of analytes from water samples were systematically investigated. The best extraction conditions involved the rapid injection of a mixture of 1.0 mL of isopropyl alcohol (as a dispersant) and 10 μL of carbon tetrachloride (as an extractant) into 10 mL of water containing 0.5 g of sodium chloride in a conical-bottom glass tube. After ultrasonication for 1.0 min and centrifugation at 5,000 rpm (10 min), the sedimented phase 1.0 μL was directly injected into the GC-MS system. The limits of quantitation (LOQs) were less than 0.6 ng/L. The precision for these analytes, as indicated by relative standard deviations (RSDs), was less than 11% for both intra- and interday analysis. Accuracy, expressed as the mean extraction recovery, was between 71 and 104%. Their total concentrations were determined in the range from 8.3 to 63.9 ng/L in various environmental samples by using a standard addition method.
    Analytical and Bioanalytical Chemistry 12/2011; 402(4):1723-30. · 3.66 Impact Factor
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    ABSTRACT: The rapid and solvent-free determination of organophosphate esters (OPEs) in aqueous samples via one-step microwave-assisted headspace solid-phase microextraction (MA-HS-SPME) followed by gas chromatography-mass spectrometry (GC-MS) analysis is described. Tri-n-butyl phosphate (TnBP) and tris-(2-ethylhexyl) phosphate (TEHP) were selected as model compounds for the method of development and validation. The effects of various extraction parameters for the quantitative extraction of these analytes by MA-HS-SPME were systematically investigated and optimized. The analytes, in a 20 mL water sample (in a 40 mL sample bottle containing 2g of NaCl, pH 3.0), were efficiently extracted by a polydimethylsiloxane-divinylbenzene (PDMS-DVB) fiber placed in the headspace when the system was microwave irradiated at 140 W for 5 min. The limits of quantification (LOQs) for TnBP and TEHP were 0.5 and 4 ng/L, respectively. Using the standard addition method, MA-HS-SPME coupled with GC-MS was utilized to determine selected OPEs in surface water and wastewater treatment plants (WWTP) influent/effluent samples. Preliminary results show that TnBP was commonly detected OPEs in these aqueous samples, the correlation coefficients (r(2)) of the standard addition curves were greater than 0.9822, indicating that the developed method appears to be a good alternative technique for analyzing OPEs in aqueous samples.
    Talanta 04/2011; 84(2):406-10. · 3.50 Impact Factor
  • Chiao-Yin Cheng, Yu-Chen Wang, Wang-Hsien Ding
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    ABSTRACT: An efficient and eco-friendly injection-port tert-butyldimethylsilylated (TBDMS) derivatization and gas chromatography-mass spectrometry (GC/MS) were developed to determine an antibacterial agent, triclosan (TCS), and its metabolite: methyltriclosan (MTCS), in wastewater and surface water samples. The effects of several parameters related to the TBDMS-derivatization process (i.e., injection-port temperature, residence time and volume of silylating agent) were investigated. This on-line derivatization-coupled large-volume (10 µL) sample introduction provides sensitive, fast and reproducible results for TCS residue analyses. Each water sample was extracted by reversed-phase C18 solid-phase extraction (SPE) cartridge, and then the recovery efficiency was evaluated using various eluting solutions. Limits of quantitation (LOQs) for MTCS and TCS were 3.0 and 1.0 ng/L in 100 mL of water samples, respectively. Intra- and inter-batch precision with their accuracy were also investigated. The precision for these analytes, as indicated by relative standard deviations (RSDs), proved to be less than 7 and 11%, respectively, for intra- and inter-batch. Accuracy, expressed as the mean recovery, was between 80 and 95%. The method was then applied to environmental water samples, showing the occurrence of TCS in both surface water and municipal wastewater treatment plant (MWTP) influent/effluent samples.
    Analytical Sciences 01/2011; 27(2):197-202. · 1.57 Impact Factor
  • Shin-Hwa Tzing, Wang-Hsien Ding
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    ABSTRACT: A reliable, sensitive and eco-friendly injection-port trimethylsilylated (TMS) derivatization and gas chromatography-tandem mass spectrometry (GC-MS/MS) with furan chemical ionization (furan-CI) method was developed to determine melamine and cyanuric acid in powdered milk samples. The effects of several parameters related to the TMS-derivatization process (i.e., injection-port temperature, residence time and volume of silylating agent) and of various CI agents were investigated. Addition of a solution (3 μL) of bis(trimethyl)silyltrifluoroacetamide (BSTFA) containing 1% trimethylchlorosilane (TMCS) reagent to a 20-μL extract from the powdered milk sample gave an excellent yield of the tris-TMS-derivatives of melamine and cyanuric acid at an injection-port temperature of 90°C. Furthermore, using furan as the CI agent in conjunction with tandem mass spectrometry provided the greatest sensitivity and selectivity of detection. The limits of quantitation (LOQs) for melamine and cyanuric acid were 0.5 and 1.0 ng/g in 0.5-g of powdered milk samples, respectively. The recoveries from spiked samples--after simple ultra-sonication with 5% dimethyl sulfoxide in acetonitrile coupled with n-hexane liquid-liquid extraction--ranged from 72% to 93% with relative standard deviations of lower than or equal to 18%. In three of four real powdered milk samples, melamine was detected at concentrations ranging from 36 to 1460 ng/g; and cyanuric acid was detected in two of these samples at concentrations of 17 and 180 ng/g.
    Journal of Chromatography A 10/2010; 1217(40):6267-73. · 4.61 Impact Factor
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    ABSTRACT: The aims of this study were to determine the concentrations of 4-nonylphenol (NP) and 4-octylphenol (OP) in 59 human milk samples and to examine related factors including mothers' demographics and dietary habits. Women who consumed over the median amount of cooking oil had significantly higher OP concentrations (0.98 ng/g) than those who consumed less (0.39 ng/g) (P < 0.05). OP concentration was significantly associated with the consumption of cooking oil (beta = 0.62, P < 0.01) and fish oil capsules (beta = 0.39, P < 0.01) after adjustment for age and body mass index (BMI). NP concentration was also significantly associated with the consumption of fish oil capsules (beta = 0.38, P < 0.01) and processed fish products (beta = 0.59, P < 0.01). The food pattern of cooking oil and processed meat products from factor analysis was strongly associated with OP concentration in human milk (P < 0.05). These determinations should aid in suggesting foods for consumption by nursing mothers in order to protect their infants from NP/OP exposure.
    Food and chemical toxicology: an international journal published for the British Industrial Biological Research Association 05/2010; 48(7):1939-44. · 2.99 Impact Factor
  • Shin-Fang Wu, Wang-Hsien Ding
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    ABSTRACT: One-step in situ microwave-assisted headspace solid-phase microextraction (MA-HS-SPME) followed by gas chromatography-mass spectrometry (GC-MS) analysis is presented as a fast and solvent-free technique to determine synthetic polycyclic musks in sewage sludge and sediment samples. Six synthetic polycyclic musks (galaxolide (HHCB), tonalide (AHTN), celestolide (ADBI), traseolide (ATII), cashmeran (DPMI) and phantolide (AHMI)) were selected in the method development and validation. The effects of extraction parameters for the quantitative extraction of these analytes by one-step MA-HS-SPME were systematically investigated. The dewatered solid sample mixed with 20-mL deionized water (containing 3 g of NaCl in a 40-mL sample-vial) was efficiently extracted by a polydimethylsiloxane-divinylbenzene (PDMS-DVB) fiber placed in the headspace when the extraction slurry was microwave irradiated at 80 W for 5 min. The limits of detection (LODs) ranged from 0.04 to 0.1 ng/g, and the limits of quantification (LOQs) ranged from 0.1 to 0.3 ng/g (fresh weight). A preliminary analysis of sludge and sediment samples revealed that HHCB and AHTN were the two most commonly detected synthetic polycyclic musks; using a standard addition method, their total concentrations were determined to range from 0.3 to 10.9 ng/g (fresh weight) with relative standard deviation (RSD) ranging from 4% to 10%.
    Journal of Chromatography A 03/2010; 1217(17):2776-81. · 4.61 Impact Factor
  • Source
    Hsiao-Wu Chung, Wang-Hsien Ding
    Analytical and Bioanalytical Chemistry 02/2010; · 3.66 Impact Factor
  • Ching-Lin Hsu, Wang-Hsien Ding
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    ABSTRACT: A rapid and environmental-friendly injection-port derivatization with gas chromatography-mass spectrometry (GC-MS) method was developed to determine selected low-molecular weight (LMW) dicarboxylic acids (from C2 to C10) in atmospheric aerosol samples. The parameters related to the derivatization process (i.e., type of ion-pair reagent, injection-port temperature and concentration of ion-pair reagent) were optimized. Tetrabutylammonium hydroxide (TBA-OH) 20 mM in methanol gave excellent yield for di-butyl ester dicarboxylate derivatives at injection-port temperature at 300 degrees C. Solid-phase extraction (SPE) method instead of rotary evaporation was used to concentrate analytes from filter extracts. The recovery from filter extracts ranged from 78 to 95% with relative standard deviation (RSD) less than 12%. Limits of quantitation (LOQs) ranged from 25 to 250 pg/m(3). The concentrations of di-carboxylated C2-C5 and total C6-C10 in particles of atmospheric aerosols ranged from 91.9 to 240, 11.3 to 56.7, 9.2 to 49.2, 8.7 to 35.3 and n.d. to 37.8 ng/m(3), respectively. Oxalic acid (C2) was the dominant LMW-dicarboxylic acids detected in aerosol samples. The quantitative results were comparable to the results obtained by the off-line derivatization.
    Talanta 12/2009; 80(2):1025-8. · 3.50 Impact Factor
  • Hsiao-Wu Chung, Wang-Hsien Ding
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    ABSTRACT: An efficient microwave-assisted extraction (MAE) procedure coupled to gas chromatography-mass spectrometry (GC-MS) with electron impact (EI) and chemical ionization (CI) has been developed to determine five organophosphate flame retardants (OPFRs) in marine and river sediments. The effects of various operating parameters on the quantitative extraction of the OPFRs through MAE were systematically investigated. Selected OPFRs were extracted from the sediments through MAE using 40 mL of acetone at 120 degrees C for 20 min. The limits of quantitation ranged from 0.1 to 0.4 ng/g (dry weight) in 2 g of the sediment samples. Moreover, as the chlorinated alkyl phosphates present no molecular ions in EI, GC-MS with furan-CI (furan-CI) was applied to confirm their determination in complex environmental samples. The recoveries of the selected OPFRs in spiked sediment samples ranged from 62% to 106% (relative standard derivation, 1-11%). The total concentrations of the selected OPFR residues in marine and river sediments ranged from 1.0 to 12.6 ng/g.
    Analytical and Bioanalytical Chemistry 09/2009; 395(7):2325-34. · 3.66 Impact Factor
  • Hsin-Hung Wu, Hsin-Chang Chen, Wang-Hsien Ding
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    ABSTRACT: An efficient microwave-assisted extraction (MAE) procedure coupled with high performance liquid chromatography-electrospray-ion-trap mass spectrometry (HPLC-ESI-ITMS) has been evaluated to determine hexabromocyclododecane diastereoisomers (alpha-, beta- and gamma-HBCD) in marine sediments. The composition of the LC mobile phase (consisting of water, methanol and acetonitrile) and the parameters of electrospray ionization (ESI) were evaluated to obtain chromatographic baseline separation and high sensitivity for the detection of these diastereoisomers. The effects of various operating parameters on the quantitative extraction of the HBCDs through MAE were systematically investigated. The three diastereoisomers were then quantitated by HPLC-ITMS employing ESI operated in the negative ionization mode. The HBCDs were extracted from the sediments through MAE using 40mL of acetone/n-hexane (1/3, v/v) at 90 degrees C for 12min. The limits of quantitation (LOQ) ranged from 25 to 40pg/g (dry weight) in 5g of the sediment samples. The recoveries of the HBCDs in spiked sediment samples ranged from 68 to 91% (relative standard derivation: 2-11%). The extraction efficiency of the MAE technique was also compared with Soxhlet extraction and pressurized liquid extraction.
    Journal of Chromatography A 09/2009; 1216(45):7755-60. · 4.61 Impact Factor

Publication Stats

429 Citations
181.01 Total Impact Points

Institutions

  • 2000–2014
    • National Central University
      • Department of Chemistry
      Taoyuan City, Taiwan, Taiwan
  • 2010–2013
    • Army Academy ROC
      Taoyuan City, Taiwan, Taiwan
  • 2009
    • National Health Research Institutes
      Miao-li-chieh, Taiwan, Taiwan
  • 2002
    • European Commission - Joint Research Centre
      • Institute for Reference Materials and Measurements
      Brussels, BRU, Belgium