固相萃取/超高效液相色谱-串联质谱法快速测定不同水体中5种人造甜味剂、6种造影剂及咖啡因

建立了快速检测不同水样(地表水、污水处理厂进水和出水)中5种人造甜味剂、6种造影剂和咖啡因的超高效液相色谱-串联质谱(UPLC-MS/MS)方法。利用HR-X固相萃取柱对过滤后的水样进行富集净化。采用Zorbax SB-C_(18)色谱柱分离,电喷雾正模式(ESI+)和负模式(ESI-)下分别以乙腈-水(10 mmol/L乙酸铵,0.01%甲酸)和乙腈-水(5 mmol/L乙酸铵,1 mmol/L Tris)为流动相,多反应监测模式(MRM)检测。各目标化合物在5~5 000μg/L范围内线性关系良好,相关系数均大于0.998。地表水、污水处理厂进水和出水的回收率为70%~120%,相对标准偏差(RSD)为0.8%~19.0%,方法检出限(MDL)分别为0.43~13.8、1.80~34.8、2.30~134 ng/L。应用该方法对广州某污水处理厂进水和出水及受纳河流河水进行检测,除阿斯巴甜、碘他拉酸、碘普罗胺、碘美普尔外,其他物质均有检出且浓度较高。该方法准确、灵敏、操作简便,适用于多种环境水样中人造甜味剂、造影剂和咖啡因的分析检测。     

Determination of fluoroquinolones in environmental waters by in-tube solid-phase microextraction coupled with liquid chromatography-tandem mass spectrometry

We developed a sensitive and useful method for the determination of five fluoroquinolones (FQs), enoxacin, ofloxacin, ciprofloxacin, norfloxacin, and lomefloxacin in environmental waters, using a fully automated method consisting of in-tube solid-phase microextraction (SPME) coupled with liquid chromatography-tandem mass spectrometry (LC/MS/MS). These compounds were analysed within 7 min by high-performance liquid chromatography (HPLC) using a CAPCELL PAK C8 column and aqueous ammonium formate (pH 3.0, 5 mM)/acetonitrile (85/15, v/v) at a flow rate of 0.2 mL/min. Electrospray ionization conditions in the positive ion mode were optimized for MS/MS detection. In order to optimize the extraction of FQs, several in-tube SPME parameters were examined. The optimum in-tube SPME conditions were 20 draw/eject cycles of 40 μL of sample at a flow-rate of 150 μL/min, using a Carboxen 1010 PLOT capillary column as an extraction device. The extracted compounds were easily desorbed from the capillary by passage of the mobile phase. Using the in-tube SPME LC/MS/MS method, good linearity of the calibration curve (r ≥ 0.997) was obtained in the concentration range from 0.1 to 10 ng/mL for all compounds examined. The limits of detection (S/N = 3) of the five FQs ranged from 7 to 29 pg/mL. The in-tube SPME method showed 60-94-fold higher sensitivity than the direct injection method (5 μL injection). This method was applied successfully to the analysis of environmental water samples without any other pretreatment and interference peaks. Several surface waters and wastewaters were collected from the area around Asahi River, and ofloxacin was detected in wastewater samples of a sewage treatment plant and other two hospitals at 17.5-186.2 pg/mL. The recoveries of FQs spiked into river water were above 81% for a 0.1 or 0.2 ng/mL spiking concentration, and the relative standard deviations were below 1.9-8.6%.     

大体积搅拌棒吸附萃取技术与热脱附-气相色谱-质谱法测定地表水中多环芳烃

基于搅拌棒吸附萃取(SBSE)技术建立了气相色谱-质谱测定地表水中16种多环芳烃(PAHs)的分析方法。该法采用多搅拌吸附棒同时富集,依次热脱附冷聚焦后进样的方式有效解决了搅拌棒吸附时间长、富集水样体积小等问题。优化后的结果表明,在0.2~10 ng/L范围内(萘为0.5~10 ng/L范围),16种PAHs的线性关系良好,相关系数(r)均0.99,方法检出限(MDL)为0.03~0.20 ng/L(萘为0.50 ng/L)。用该方法对钱塘江流域地表水进行测定,共检测出11种PAHs,含量为0.13~1.57 ng/L,不同添加水平下的加标回收率为75.6%~108.9%。该法可应用于地表水样品中该类物质的超痕量检测。     

Simultaneous determination of isoflavones and lignans at trace levels in natural waters and wastewater samples using liquid chromatography/electrospray ionization ion trap mass spectrometry

A high-performance liquid chromatography/electrospray ionization ion trap mass spectrometry (HPLC/ESI-MSn) method has been developed for the trace determination of phytoestrogens in aquatic environmental samples. The method includes solid-phase extraction (SPE) and analysis using liquid chromatography/electrospray ionization ion trap mass spectrometry. The aquatic environmental samples, influent of a wastewater treatment plant (WWTP) and creek water, were adjusted to pH approximately 5 before extraction. The analyzed phytoestrogens were identified by an MSn method and quantified against a deuterated internal standard (genistein-3',5',6,8-D4). In negative ion mode, 0.1% formic acid was employed in acetonitrile/water mobile phase. The method detection limits ranged from 0.5 to 10 ng/L in WWTP influent and from 0.1 to 5 ng/L in creek water. Average SPE recoveries for the analyzed phytoestrogens ranged from 85 to 95%, with a relative standard deviation (RSD) (%) ranging from 3.9 to 6.5. The concentrations of the six analyzed phytoestrogens varied from 0.2 to 600 ng/L with high levels of enterolignans (enterolactone and enterodiol) found in the collected wastewater. The method is shown to be suitable for the determination of phytoestrogens in aquatic environmental samples at nano- and sub-nanogram per liter levels.     

固相萃取-超高效液相色谱-电喷雾串联质谱法同时测定地表水中16种全氟有机化合物

建立了固相萃取-超高效液相色谱-电喷雾串联三重四极杆质谱联用技术分析水中16种全氟有机化合物的高通量检测方法。样品经WAX固相萃取柱富集和净化后,采用Waters ACQUITY UPLC^TM BEH C₁₈色谱柱,含2 mmol/L乙酸铵的甲醇和含2 mmol/L乙酸铵的水作为流动相进行梯度洗脱,质谱采用电喷雾负离子电离,多反应监测模式检测。16种全氟有机化合物在0.5~100 μg/L或1.0~100 μg/L浓度范围内线性关系良好,相关系数为0.9987~0.9999,方法的检出限为0.06~0.46 ng/L;高、中、低3个添加水平的回收率为67.6%~103%,相对标准偏差为2.94%~12.0%。结果表明,该方法灵敏、准确且检测范围广,分析速度快,是一种适于实际水样中全氟有机化合物检测分析的方法。     

Simultaneous determination of tryptophan, kynurenine, kynurenic and xanthurenic acids in honey by liquid chromatography with diode array, fluorescence and tandem mass spectrometry detection

A liquid chromatography method using diode array-fluorescence detection and atmospheric pressure chemical ionization mass spectrometry (LC-DAD-FLD and LC–APCI-MS/MS) was developed to quantify the levels of tryptophan (TRP), kynurenine (KYN), kynurenic (KYNA) and xanthurenic (XA) acids in honey. This procedure involved isolating the compounds of interest via solid-phase extraction (SPE) with mixed-mode polymeric cartridges. Chromatographic separation of the analytes was performed in isocratic mode on a Synergi 4μ Hydro-RP 80Å (150 × 4.60 mm i.d.) analytical column at 30 °C. The mobile phase of 20 mM ammonium formate (pH 4) and methanol was passed at a flow rate of 0.5 mL/min. In replicate sets of spiked honey samples, the average analyte recoveries ranged from 60 to 98% for TRP, 55 to 120% for KYN, 65 to 106.5 for KYNA and 56 to 114% for XA. Detection limits ranged from 4 to 36 μg/kg for LC-DAD-FLD to 0.2 and 1.0 μg/kg for LC–APCI-MS/MS. A strong matrix effect was found when MS/MS was employed, necessitating calibration using the standard addition method on matrix-matched standards for each honey type. The method was used to quantify each of the compounds of interest in 17 honey samples of distinct botanical origins.     

Determination of cyclophosphamide and ifosfamide in sewage effluent by stable isotope-dilution liquid chromatography-tandem mass spectrometry

A reliable and specific method was developed for the determination of the cytotoxic drugs cyclophosphamide and ifosfamide in sewage effluent. The most successful combination was found to be Strata-X solid-phase extraction followed by Florisil^® clean-up with analysis by liquid chromatography–tandem mass spectrometry. Quantification by internal standardisation was achieved using custom synthesised d4-cyclophophosphamide. The mass spectrometer was operated in highly selective reaction monitoring (HSRM) mode, which significantly reduced matrix noise and improved sensitivity. Although it suffered from some ionisation suppression, electrospray ionisation (ESI) was found to give an order of magnitude better sensitivity in terms of limit of detection than atmospheric pressure chemical ionisation (APCI). Using final effluent from two different sewage treatment plants, the method was validated following official European guidelines and shown to be a high performance tool for routine analysis at the sub-nanogram per litre level. Depending on the matrix, the limit of detection for cyclophosphamide was between 0.03 ng/L and 0.12 ng/L and for ifosfamide between 0.05 ng/L and 0.09 ng/L. For cyclophosphamide the accuracy and precision, tested at 1.7 ng/L, were 98–109% and ≤13%, CV respectively. For ifosfamide the accuracy and precision, tested at 1.1 ng/L, were 98–113% and ≤15% CV, respectively. Depending on the sample matrix the absolute recovery of the internal standard was between 57% and 70%. The method was tested by analysis of spot samples taken from the final effluent discharges of two sewage treatment plants; the first using a conventional trickling filter treatment process and second employing activated sludge followed by ultra violet treatment. Cyclophosphamide was detected at 0.19 ng/L at the first plant and at the second detected at 3.7 ng/L and 3.5 ng/L, before and after the UV treatment process; ifosfamide was not detectable at either plant.     

Analysis of off-flavors in the aquatic environment by stir bar sorptive extraction–thermal desorption–capillary GC/MS/olfactometry

The off-flavor compounds 2-methylisoborneol (MIB), geosmin, 2,4,6-trichloroanisole, 2,3,6-trichloroanisole, 2,3,4-trichloroanisole, and 2,4,6-tribromoanisole were analyzed in water samples by stir bar sorptive extraction (SBSE) followed by on-line thermal desorption (TD) capillary GC/MS. Quantification was performed using the MS in the single-ion-monitoring mode (SIM) with 2,4,6-trichloroanisole-D(5 )as internal standard. Quantification limits are 0.1-0.2 ng L(-1) for the haloanisoles, 0.5 ng L(-1) for geosmin, and 1 ng L(-1) for MIB. The relative standard deviations at the quantification limit ranged from 7 to 14.6%. SBSE recovery was evaluated by spiking real water samples and varied from 87 to 117%. More than twenty samples per day can be analyzed by SBSE-TD-capillary GC-MS. The same technique in combination with olfactometry was used to elucidate unknown odorous compounds in water samples.     

Hollow fiber supported liquid membrane extraction for ultrasensitive determination of trace lead by portable tungsten coil electrothermal atomic absorption spectrometry

Hollow fiber supported liquid membrane extraction (HF-SLME) was used to separate and enrich trace lead from a large volume of 250 mL water sample to a final tiny volume of 30 μL of 1-octanol, 5 μL of which was inject into a tungsten coil electrothermal atomic absorption spectrometer (W-coil ET-AAS) for determination of lead. Some important parameters that influenced the extraction and determination were investigated in detail, such as the concentration of ammonium pyrrolidine dithiocarbamate (APDC), pH of sample solution, stirring rate, extraction time, pyrolysis current, atomization current, carrier gas flow rate, as well as interferences. Under the optimized conditions, a practical enrichment factor of 499 and a limit of detection (3σ) of 0.2 ng mL^{− 1} were obtained. The calibration curve was linear in the range of 0.5–10 ng mL^{− 1}. The relative standard deviation (RSD) was 5.6% for five measurements of a 4 ng mL^{− 1} lead standard solution. The accuracy of this method was examined by the analysis of certified reference water samples (GBW(E)080398 and GSBZ(E) 50009-88) for lead. Finally, the proposed method was applied to the determination of lead in local tap water, pond water and river water, with recoveries in the range of 96–109% for spiked samples.     

Ultra-trace level determinations of benzidine and dichlorobenzidine residues in surface water by liquid chromatography-electrospray ionization tandem mass spectrometry

A liquid chromatography-electrospray ionization tandem mass spectrometric method (LC-ESI-MS/MS) has been developed for the determination of benzidine (BZ) and 3, 3′-dichlorobenzidine (DCBZ) from surface water. Parent ion of DCBZ gave strong signal with ESI by dissolving with 15?mM ammonium formate, which is also used as mobile phase. Deuterated BZ (d8-BZ) was chosen as the internal standard (IS). BZ and DCBZ were extracted by solid-phase extraction on Oasis hydrophilic-lipophilic balance (HLB) from water at pH 8.0. The coefficients of variation of BZ and DCBZ were less than 13.1% and the detection limits were 0.004?ng?L^?1 for BZ and 0.7?ng?L^?1 for DCBZ using 0.5?L surface water. The detection limit shows fair lower value than the water quality criteria for BZ and DCBZ established by the US EPA. When the proposed method was used to analyze the target compounds in sixteen surface water samples, BZ was detected in a concentration range of 0.15–2.33?ng?L^?1 in four of sixteen surface water samples     

固相萃取/高效液相色谱-串联质谱法同时检测环境水样中24种农药残留

建立了一种固相萃取/高效液相色谱-串联质谱(SPE/HPLC-MS/MS)同时检测水体中24种农药的分析方法。样品用乙腈提取后,经固相萃取小柱富集净化。以乙腈-0.1%(体积分数)甲酸水溶液为流动相梯度洗脱,在电喷雾离子源正离子模式下(ESI+)采用多反应监测(MRM)模式检测。结果显示,24种农药在1~200μg/L范围内具有良好的线性关系,相关系数(r2)均不小于0.998,水样中3个添加水平(5、20、100μg/L)下的回收率为65.9%~127.8%,相对标准偏差(RSD)为0.7%~14.2%;方法检出限为0.05~0.71 ng/L。采用该方法对大连地区10个河流入海口及2个水库的水样进行了检测,12个站位的样品中共检出10种农药,质量浓度为0.2~558.3 ng/L。结果表明,所建立的SPE/HPLC-MS/MS方法高效、灵敏、可靠,可用于实际水体中多种农药的同时检测。     

Speciation of butyl and phenyltin compounds using dispersive liquid-liquid microextraction and gas chromatography-flame photometric detection

Dispersive liquid-liquid microextraction and gas chromatography-flame photometric detection (DLLME-GC-FPD) were performed for the speciation of butyl and phenyltin compounds in water samples after derivatization with sodium tetraethylborate (NaBEt4). Some important parameters, such as pH, amount of NaBEt4, derivatization time, kind and volume of extraction and disperser solvents, extraction time and salt effect were investigated and optimized. High enrichment factors (825-1036) and low detection limits (0.2-1 ng L(-1)) were obtained under the optimum conditions. The calibration graphs were linear in the range of 0.5-1000 ng L(-1) (as Sn) for the target analytes. The relative standard deviations (RSDs) for the extraction of 20 ng L(-1) (as Sn) of butyl and phenyltin compounds varied from 2.3 to 5.9% (n=7) and from 4.1 to 8.8% (n=7) with and without using internal standard, respectively. Seawater and river water samples were successfully analyzed using the proposed method and the relative recoveries of the studied compounds in the water samples, at spiking levels of 10.0 and 100 ng L(-1) (as Sn) were obtained to be 82.5-104.7%.     

Development of a multi-residue analytical methodology based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) for screening and trace level determination of pharmaceuticals in surface and wastewaters

This paper describes development, optimization and validation of a method for the simultaneous determination of 29 multi-class pharmaceuticals using off line solid phase extraction (SPE) followed by liquid chromatography-triple quadrupole mass spectrometry (LC-MS-MS). Target compounds include analgesics and non-steroidal anti-inflammatories (NSAIDs), lipid regulators, psychiatric drugs, anti-histaminics, anti-ulcer agent, antibiotics and β-blockers. Recoveries obtained were generally higher than 60% for both surface and wastewaters, with exception of several compounds that yielded lower, but still acceptable recoveries: ranitidine (50%), sotalol (50%), famotidine (50%) and mevastatin (34%). The overall variability of the method was below 15%, for all compounds and all tested matrices. Method detection limits (MDL) varied between 1 and 30 ng/L and from 3 to 160 ng/L for surface and wastewaters, respectively. The precision of the method, calculated as relative standard deviation (R.S.D.), ranged from 0.2 to 6% and from 1 to 11% for inter and intra-day analysis, respectively. A detailed study of matrix effects was performed in order to evaluate the suitability of different calibration approaches (matrix-matched external calibration, internal calibration, extract dilution) to reduce analyte suppression or enhancement during instrumental analysis. The main advantages and drawbacks of each approach are demonstrated, justifying the selection of internal standard calibration as the most suitable approach for our study. The developed analytical method was successfully applied to the analysis of pharmaceutical residues in WWTP influents and effluents, as well as in river water. For both, river and wastewaters, the most ubiquitous compounds belonged to the group of anti-inflammatories and analgesics, antibiotics, the lipid regulators being acetaminophen, trimethoprim, ibuprofen, ketoprofen, atenolol, propranolol, mevastatin, carbamazepine and ranitidine the most frequently detected compounds.     

凝固漂浮有机液滴-分散液液微萃取结合高效液相色谱法同时测定地表水中多环芳烃和酞酸酯

多环芳烃和酞酸酯是国际公认的优控污染物,因此准确快速地测定水中多环芳烃和酞酸酯非常重要。凝固漂浮有机液滴-分散液液微萃取（DLLME-SFO）是一种简便、快速、环境友好、灵敏度高的样品前处理技术。采用DLLME-SFO同时测定地表水中多环芳烃和酞酸酯的分析方法鲜有报道。该文采用凝固漂浮有机液滴-分散液液微萃取富集技术,结合高效液相色谱紫外/荧光法,建立了同时测定地表水中16种多环芳烃和6种酞酸酯的分析方法。考察优化了影响萃取效率的主要因素,包括萃取剂的种类和用量、分散剂的种类和用量、萃取时间和离子强度等。优化后的萃取实验条件为：5.0 mL水样,10 μL十二醇为萃取溶剂,500 μL甲醇为分散溶剂,涡旋振荡时间2 min,氯化钠用量0.2 g。目标化合物经多环芳烃专用色谱柱（SUPELCOSIL^TM LC-PAH,150 mm×4.6 mm,5 μm）结合乙腈-水梯度洗脱分离,16种多环芳烃除苊烯外采用荧光检测,苊烯和6种酞酸酯采用紫外检测,外标法定量。结果表明,22种目标化合物的基质加标回收率为60.2%~113.5%,相对标准偏差为1.9%~14.3%;多环芳烃和酞酸酯的检出限分别为0.002~0.07 μg/L和0.2~2.2 μg/L;多环芳烃和酞酸酯的定量限分别为0.006~0.23 μg/L和0.8~7.4 μg/L。该方法简便、快速,环境友好,灵敏度高,可用于地表水中多环芳烃和酞酸酯的快速分析检测。     

超高效液相色谱-串联质谱法同时检测地表水中18种药物与个人护理品的残留量

采用固相萃取对水样进行预处理,建立了同时检测地表水中包括抗生素、β-阻滞剂、驱蚊剂、抗癫痫药、中枢神经兴奋剂、血脂调节剂、非甾体抗炎药、杀菌消毒剂在内的18种药物与个人护理品的超高效液相色谱-串联质谱分析方法。采用中性条件萃取水样,控制上样流速为2 mL/min,用甲醇-乙腈(1:1, v/v)溶液洗脱。纯水中的平均加标回收率为53.9%～112%,相对标准偏差为2.6%～15.3%(n=6);以地表水样加标100 ng/L为样品,目标分析物平均回收率为45.1%～156.6%,相对标准偏差为2.4%～15.7%(n=6)。结果表明,本方法可同时精确检测地表水样中的18种分析物,方法验证结果表明所建立的方法可靠。用该方法分析杭州余杭塘河水,结果检出9种分析物,其中咖啡因平均质量浓度达550.7 ng/L。结果表明该方法可靠。     

Simultaneous determination of benzotriazoles and ultraviolet filters in ground water, effluent and biosolid samples using gas chromatography-tandem mass spectrometry

A new method using gas chromatography-tandem mass spectrometry (GC-MS/MS) was developed for the determination of four benzotriazoles, i.e. benzotriazole (BT), 5-methylbenzotriazole (5-TTri), 5-chlorobenzotriazole (CBT), 5,6-dimethylbenzotriazole (XTri), and six UV filters, i.e. benzophenone-3 (BP-3), 3-(4-methylbenzylidene)camphor (4-MBC), octyl 4-methoxycinnamate (OMC), 2-(3-t-butyl-2-hydroxy-5-methylphenyl)-5-chloro benzotriazole (UV-326), 2-(2'-hydroxy-5'-octylphenyl)-benzotriazole (UV-329), and octocrylene (OC) in ground water, effluent and biosolid samples. Solid phase extraction (SPE) and pressurized liquid extraction (PLE) were applied as the preconcentration method for water samples (ground water and effluent) and biosolid samples, respectively. The optimized method allowed us to quantify all target compounds with the method detection limits ranging from 0.29 to 11.02 ng/L, 0.5 to 14.1 ng/L and 0.33 to 8.23 ng/g in tap water, effluent and biosolid samples, respectively. The recoveries of the target analytes in tap water, effluent and biosolid samples were 70-150%, 82-127% and 81-133%, respectively. The developed analytical method was applied in the determination of these target compounds in ground water, effluent and biosolid samples collected from Bolivar sewage treatment plants in South Australia. In effluent samples, the target compounds BT, 5-TTri, CBT, XTri and BP-3 tested were detected with the maximum concentration up to 2.2 μg/L for BT. In biosolid samples, eight out of ten compounds tested were found to be present at the concentrations ranging between 18.7 ng/g (5-TTri) and 250 ng/g (4-MBC).     

Graphene‐coated fiber for solid‐phase microextraction of triazine herbicides in water samples

Graphene is a novel and interesting carbon material that could be used for the separation and purification of some chemical compounds. In this investigation, graphene was used as a novel fiber‐coating material for the solid‐phase microextraction (SPME) of four triazine herbicides (atrazine, prometon, ametryn and prometryn) in water samples. The main parameters that affect the extraction and desorption efficiencies, such as the extraction time, stirring rate, salt addition, desorption solvent and desorption time, were investigated and optimized. The optimized SPME by graphene‐coated fiber coupled with high‐performance liquid chromatography‐diode array detection (HPLC‐DAD) was successfully applied for the determination of the four triazine herbicides in water samples. The linearity of the method was in the range from 0.5 to 200 ng/mL, with the correlation coefficients (r) ranging from 0.9989 to 0.9998. The limits of detection of the method were 0.05‐0.2 ng/mL. The relative standard deviations varied from 3.5 to 4.9% (n=5). The recoveries of the triazine herbicides from water samples at spiking levels of 20.0 and 50.0 ng/mL were in the range between 86.0 and 94.6%. Compared with two commercial fibers (CW/TPR, 50 μm; PDMS/DVB, 60 μm), the graphene‐coated fiber showed higher extraction efficiency.     

固相萃取-液相色谱-串联质谱法同时测定水中14种短链和长链全氟化合物

建立了固相萃取-超高压液相色谱-三重四极杆质谱同时测定水中14种短链和长链全氟化合物（PFCs）的方法。水样经WAX混合型固相萃取小柱富集和净化后,采用BEH C18色谱柱、甲醇和5 mmol/L乙酸铵水溶液作为流动相进行梯度洗脱,质谱采用多反应监测模式,内标法定量分析。14种PFCs在0.1~50 μg/L范围内线性关系良好,相关系数大于0.99,方法检出限和定量限分别为0.09~1.15 ng/L和0.29~3.85 ng/L。在2、10和20 ng/L加标水平下,8种PFCs的平均回收率为85.0%、120.2%和117.4%,平均相对标准偏差为9.2%、9.0%和6.6%,6种PFCs的回收率相对较低,主要由于其在瓶/管壁上的吸附作用导致。应用本方法分析某淡水湖水样,检出4种短链和5种长链PFCs,质量浓度为41.29~49.05 ng/L和98.43~111.02 ng/L。结果表明该方法适用于对环境水体中短链和长链PFCs的同时分析测定。     

改进的QuEChERS结合超高效液相色谱-串联质谱法快速测定地表水中双酚类物质

建立了同时测定地表水中8种双酚类物质(BPs)的超高效液相色谱-串联质谱(UPLC-MS/MS)分析方法.方法 基于QuEChERS处理技术,选用乙酸乙酯为提取剂,从基质效应(ME)和萃取回收率(RE)两方面对过程效率(PE)进行优化,确定了50 mg N-丙基乙二胺(PSA)和50 mg石墨化炭黑(GCB)混合吸附剂...     

Cellulose membrane modified with polypyrrole as an extraction device for the determination of emerging contaminants in river water with gas chromatography–mass spectrometry

In this study, a simple, efficient, and reusable device based on cellulose membranes modified with polypyrrole was developed to extract 14 emerging contaminants from aqueous matrices. For chemical polymerization, a low‐cost cellulose membrane was immersed in 0.1 mol/L pyrrole and 0.5 mol/L ammonium persulfate for 40 min in an ice/water bath. The cellulose membranes modified with polypyrrole were accommodated in a polycarbonate holder suitable for solid‐phase extraction disks. Solid‐phase extraction parameters that affect extraction efficiency, such as sample volume, pH, flow rate, and desorption were optimized. Subsequently, determination of target compounds was performed by gas chromatography with mass spectrometry. The linear range for analytes ranged from 0.05 to 500 μg/L, with coefficients of determination above 0.990. The limits of quantification varied between 0.05 and 10 μg/L, with relative standard deviations lower than 17%. The performance of the proposed cellulose membranes modified with polypyrrole device for real samples was evaluated after extraction of emerging contaminants from a river water sample from the city of Curitiba, Brazil. Bisphenol A (6.39 μg/L), caffeine (17.83 μg/L), and paracetamol (19.28 μg/L) were found in these samples.