碘化钾―甲基异丁基甲酮萃取―火焰原子吸收法测定土壤中的痕量铅

土壤样品经微波消解,在优化的条件下,用碘化钾―甲基异丁基甲酮萃取,采用火焰原子吸收光谱法测定其中的铅。结果表明,在盐酸质量分数为1%～2%,萃取时间为2 min,平衡时间为15 min,样品中的铅能被定量萃取。方法检出限为0.1 mg/kg。方法用于土壤标准样品测定,测定值与标准值相符,相对标准偏差为1.2%～1.4%,相对误差为0.8%～2.5%。实际土壤样品的测定结果显示,回收率为99.8%～100.4%。     

固相微萃取―气相色谱―质谱联用方法分析人参中的挥发性物质

采用固相微萃取―气相色谱―质谱联用(SPME-GC-MS)的方法测定了人参中的挥发性物质,并对萃取头类型、萃取温度、萃取时间进行了优化。结果表明,当采用100μm聚二甲基硅氧烷(PDMS)的萃取头(非极性),80℃萃取30 min时,萃取效果最好。结果显示,人参中主要的挥发性物质为γ-榄香烯和β-古芸烯等。     

气相色谱―质谱法测定仿真饰品中磷酸酯类增塑剂含量

建立了仿真饰品中6种磷酸酯类增塑剂含量的气相色谱―质谱测定法。对提取方法、色谱条件及质谱参数进行了研究。结果表明,采用正己烷/丙酮(体积比1∶1)微波萃取样品35 min可获得良好的提取效果。所建立的微波萃取―气相色谱―质谱法的定量限为1～2.5 mg/kg,在1～2个数量级浓度范围内,线性相关系数R2在0.999以上,在三个添加水平下回收率在86.63%～98.13%之间。对市售9种塑料仿真饰品的测定结果表明磷酸酯的存在风险极低。     

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。     

固相萃取-气相色谱法测定地下水中痕量酞酸酯的研究

本文建立了固相萃取-气相色谱法定量分析地下水中酞酸酯类（PAEs）有机污染物的方法。利用正交试验和单因素实验对影响回收率的4个主要因素（洗脱溶剂种类、水样体积、洗脱溶剂体积、固相萃取小柱填料量）进行了萃取条件的优化。综合考虑各方面因素后确定的最佳萃取条件为：二氯甲烷和丙酮为洗脱剂,体积8mL、0．5L水样、柱填料500mg。方法线性范围0．05～10．00μg／L,检出限0．05～0．341ng／L,相对标准偏差0．038％～1．107％。该方法应用于江汉平原地下水中PAEs测定,取得满意结果。     

基于超声辅助原位生成低共熔溶剂的分散液-液微萃取-悬浮固化结合毛细管电泳测定环境水样中氟喹诺酮

基于超声辅助原位生成低共熔溶剂（DES）的分散液-液微萃取-悬浮固化（UA-IF-DLLMESFDES）并结合大体积样品堆积毛细管电泳,建立了对环境水样中加替沙星、洛美沙星、环丙沙星和氟罗沙星4种氟喹诺酮类药物（FQs）进行萃取和测定的新方法。实验筛选出甲基三辛基溴化铵作为氢键受体（HBA）,庚酸为氢键供体（HBD）,以原位生成方法制备的DES为萃取剂,并对DES的种类及用量、原位生成条件、盐用量、涡旋时间等影响萃取效率的实验条件进行了优化。结果表明,在最佳实验条件下,4种目标物的检出限（S/N=3）和定量下限（S/N=10）分别为0.6～5.5μg/L和2.0～18.3μg/L,富集倍数为89～129,日内和日间相对标准偏差（RSD）分别为3.5%～5.9%和4.5%～7.1%,加标回收率为75.6%～110%。所建立的方法成功应用于实际水样中4种FQs的检测。     

基于杯［6］芳烃萃取头的固相微萃取-气相色谱法测定啤酒中痕量的酞酸酯类化合物

选用自制杯［6］芳烃溶胶-凝胶固相微萃取(SPME)萃取头,建立了顶空SPME与气相色谱联用检测啤酒中8种酞酸酯(PAEs)的方法。采用L25(56)正交设计对萃取条件进行了优化,所得方法检出限为0.003～3.429 μg/L,相对标准偏差不超过13.5%,加标回收率为86.3%～109.3%。采用标准加入法对3种瓶装啤酒中PAEs进行了检测,结果表明邻苯二甲酸二(2-乙基己)酯(DEHP)是啤酒中最主要的酞酸酯类污染物,含量最高达5.24 μg/L。迁移试验表明,瓶装啤酒所用塑料垫圈中高含量的DEHP可能成为酒体中PAEs的一种来源,且延长贮存时间、提高贮存温度和振荡都能加快垫圈中DEHP的迁移。     

固相膜萃取-超声解吸-气相色谱-质谱法分析水中酞酸酯类化合物

酞酸酯(PAEs)是一种常用的增塑剂,由于其广泛应用已经对环境造成了污染.本研究建立了固相膜萃取-超声解吸-气相色谱-质谱分析水中酞酸酯类化合物的方法.对萃取条件、解吸条件进行了优化,确定了最佳的实验条件.在水浴温度40℃,超声功率50%的条件下超声7 min,测定水中PAEs的检出限(S/N>3)在0.05 ~0.26 μg/L之间;对不同基质空白样品进行加标回收实验,回收率在76.2%~112.3%之间,相对标准偏差小于10%.     

液液萃取-气相色谱/质谱法测定地表水中的15种酞酸酯

酞酸酯是《地表水环境质量标准》要求的必测项目,但其实验本底值一直是准确定量的不确定因素,本文探讨了实验过程中引进酞酸酯污染的主要环节及其主要来源,建立了液液萃取-气相色谱/质谱联用测定地表水中15种酞酸酯的方法。实验结果表明,测试过程中主要的本底为邻苯二甲酸二甲酯、二乙酯、二异丁酯、二丁酯及邻苯二甲酸(2-乙基己基)酯5类物质,溶剂是主要来源。扣除实验本底后,15种酞酸酯的线性相关系数均大于0.99,空白水样高、低浓度的加标回收率均在70%~110%之间,方法的精密度(RSD)10%,当采样体积为1.0L时,15种酞酸酯的方法检出限为0.04~0.16μg/L。3种城市地表水样的加标回收率在74%~105%之间。     

超声提取辅助顶空式固相微萃取/气相色谱-质谱法测定塑胶跑道面层中7种挥发性硫化物

建立了一种检测塑胶跑道面层中二甲基硫（DMS）、二硫化碳（CS2）、甲基乙基硫（MES）、二乙基硫（DES）、二甲基二硫（DMDS）、二乙基二硫（DEDS）、二甲基三硫（DMTS）7种挥发性硫化物（VSCs）的超声提取辅助顶空式固相微萃取/气相色谱-质谱（HS-SPME/GC-MS）分析方法。实验优化了顶空固相微萃取的萃取条件、超声提取条件及气相色谱-质谱参数。在优化条件下,DES、DMDS的线性范围为5～500 ng/g,其余5种VSCs的线性范围为10～500 ng/g,相关系数（r）为0.984 7～0.998 9,方法的检出限（S/N=3）为0.4～1.4 ng/g,定量下限（S/N=10）为1.3～4.7 ng/g。在低、中、高3个加标水平下的平均回收率为89.6%～104%,相对标准偏差（RSD,n=6）为3.5%～12%。该方法可实现分离、富集和进样一体化,适用于塑胶跑道面层中VSCs含量的日常检测。     

Simple and rapid determination of phthalates using microextraction by packed sorbent and gas chromatography with mass spectrometry quantification in cold drink and cosmetic samples

A simple and rapid method using microextraction by packed sorbent coupled with gas chromatography and mass spectrometry has been developed for the analysis of five phthalates, namely, diethyl phthalate, benzyl‐n‐butyl phthalate, dicyclohexyl phthalate, di‐n‐butyl phthalate, and di‐n‐propyl phthalate, in cold drink and cosmetic samples. The various parameters that influence the microextraction by packed sorbent performance such as extraction cycle (extract–discard), type and amount of solvent, washing solvent, and pH have been studied. The optimal conditions of microextraction using C₁₈ as the packed sorbent were 15 extraction cycles with water as washing solvent and 3 × 10 μL of ethyl acetate as the eluting solvent. Chromatographic separation was also optimized for injection temperature, flow rate, ion source, interface temperature, column temperature gradient and mass spectrometry was evaluated using the scan and selected ion monitoring data acquisition mode. Satisfactory results were obtained in terms of linearity with R² >0.9992 within the established concentration range. The limit of detection was 0.003–0.015 ng/mL, and the limit of quantification was 0.009–0.049 ng/mL. The recoveries were in the range of 92.35–98.90% for cold drink, 88.23–169.20% for perfume, and 88.90–184.40% for cream. Analysis by microextraction by packed sorbent promises to be a rapid method for the determination of these phthalates in cold drink and cosmetic samples, reducing the amount of sample, solvent, time and cost.     

Ultrasound-assisted liquid-phase microextraction based on a nanostructured supramolecular solvent

Novel ultrasonically enhanced supramolecular solvent microextraction (USESSM) then high-performance liquid chromatography with ultraviolet detection have been used for extraction and determination of phthalates in water and cosmetics. Coacervates consisting of decanoic acid-based nano-structured aggregates, specifically reverse micelles, have been used the first time as solvents for ultrasound-assisted emulsification microextraction (USAEME). Sonication accelerated mass transfer of the target analytes into the nano-structured solvent from the aqueous sample, thus reducing extraction time. Several conditions affecting extraction efficiency, for example the concentrations of major components of the supramolecular solvent (tetrahydrofuran and decanoic acid), sample solution pH, salt addition, and ultrasonication time, were investigated and optimized. Under the optimum conditions, preconcentration of the analytes ranged from 176 to 412-fold and the linear range was 0.5–100 μg?L^?1, with correlation coefficients (R ²)?≥?0.9984. The detection sensitivity of the method was excellent, with limits of detection (LOD, S/N?=?3) in the range 0.10–0.70 μg?L^?1 and precision in the range 4.1–11.7 % (RSD, n?=?5). This method was successfully used for analysis of phthalates in water and cosmetics, with good recovery of spiked phthalates (91.0–108.5 %).     

Development and validation of methods for the trace determination of phthalates in sludge and vegetables

A routine method which is simple, quick and precise has been set up and validated for phthalate analysis in environmental samples (tomato plants and sewage sludges). Six phthalates have been studied simultaneously: dimethylphthalate, diethylphthalate, di-n-butylphthalate, n-butylbenzylphthalate, di-2-ethyl-hexyl phthalate (DEHP) and di-n-octylphthalate. Optimization of sample, solvent extraction uses a Soxtec apparatus and extract purification with an a solid-phase extraction cartridge allows between 90 and 110% recovery of phthalates. Precise, sensitive and selective identification and quantifying of analytes is by GC-MS in the single ion monitoring mode. This protocol allows analytes with concentrations as low as 10 microg/kg dry matter (DM) to be determined from small (1-2 g DM) samples. This analytical method has been applied to the phthalate transfer study for agricultural recycling of sludges, where phthalate bioavailability has been studied in aquiculture using two types of experiments. Tomatoes have been grown in containers where the trace organics have been directly introduced as pure substances, and in a second experiment under the same growth conditions, sewage sludge has replaced the pure substances. Transfer of these trace organics has been followed into the various parts of the tomato plant and in general only the DEHP is worthy of note although its percentage transfer remains very low even in an experiment designed to maximize this.     

Simultaneous determination of 22 phthalate esters in polystyrene food‐contact materials by ultra‐performance convergence chromatography with tandem mass spectrometry

A method for the determination of 22 phthalate esters in polystyrene food‐contact materials has been established using ultraperformance convergence chromatography with tandem mass spectrometry. In this method, 22 phthalate esters were analyzed in <3.5 min on an ACQUITY Tours 1‐AA column by gradient elution. The mobile phase, the compensation solvent, the flow rate of mobile phase, column temperature, and automatic back pressure regulator pressure were optimized, respectively. There was a good linearity of 20 phthalate esters with a range of 0.05–10 mg/L, diisodecyl phthalate and diisononyl phthalate were 0.25–10 mg/L, and the correlation coefficients of all phthalates were higher than 0.99 and those of 16 phthalates were higher than 0.999. The limits of detection and the limits of quantification of 15 phthalates were 0.02 and 0.05 mg/kg, meanwhile diallyl phthalate, diisobutyl phthalate, dimethyl phthalate, di‐n‐butyl phthalate, and di(2‐ethylhexyl) phthalate were 0.05 and 0.10 mg/kg, and diisodecyl phthalate and diisononyl phthalate were 0.10 and 0.25 mg/kg. The spiked recoveries were in the range of 76.26–107.76%, and the relative standard deviations were in the range of 1.78–12.10%. Results support this method as an efficient alternative to apply for the simultaneous determination of 22 phthalate esters in common polystyrene food‐contact materials.     

Phthalates determination in pharmaceutical formulae used in parenteral nutrition by LC-ES-MS: importance in public health

A method for determining a group of phthalate esters in pharmaceutical formulae used in parenteral nutrition samples (with and without vitamins) has been developed. The phthalic acid esters (PAEs) studied were dimethyl phthalate, diethyl phthalate, butyl benzyl phthalate, dibutyl phthalate, di-(2-ethylhexyl) phthalate, and dioctyl phthalate. This group of phthalates was determined by high performance liquid chromatography (HPLC)–electrospray ionization–mass spectrometry, working in positive ion mode. The phthalates analyzed were extracted from the sample using hexane and sodium hydroxide. The hexane was then evaporated, and the compounds were redissolved in acetonitrile. The compounds were separated by HPLC working in gradient mode with acetonitrile-ultrapure water starting from 5% to 75% acetonitrile in 5 min, followed by isocratic elution for 27 min. Standard calibration curves were linear for all the analytes over the concentration range 10–250 μg L⁻¹. The method was precise (with RSD from 3.3% to 12.9%) and sensitive. The proposed analytical method has been applied to the analysis of these compounds in different pharmaceutical formulae (with different compositions) for parenteral nutrition samples in order to check the presence of phthalates and determine their concentration.     

高效液相色谱-串联质谱法同时测定人尿液中7种邻苯二甲酸酯代谢物

建立了同时检测人尿液中7种邻苯二甲酸酯代谢物的高效液相色谱-串联三重四极杆质谱法。尿液经酶水解后,采用萃取柱净化,以2%(v/v)甲酸甲醇溶液为洗脱剂,经苯基柱分离,以0.1%(v/v)乙酸水溶液和0.1%(v/v)乙酸乙腈溶液为流动相进行梯度洗脱,采用电喷雾离子源负离子模式和多反应监测模式采集信号,用同位素内标法进行定量分析。尿液中7种邻苯二甲酸酯代谢物在0.2~200.0 μg/L范围内定量离子的相对峰面积比值与质量浓度均呈良好线性关系(r≥0.99976);检出限(LOD)为13.43~80.21 ng/L,定量限为44.77~267.37 ng/L; 3个水平的加标回收率为88.8%~108.9%,日内和日间精密度均不大于17.05%。该方法可同时准确、灵敏、简便地测定人尿液中7种邻苯二甲酸酯代谢物的暴露水平。     

Preparation of polypyrrole-coated magnetic particles for micro solid-phase extraction of phthalates in water by gas chromatography-mass spectrometry analysis

In this work, polypyrrole (PPy)-coated Fe(3)O(4) magnetic microsphere were successfully synthesized, and applied as a magnetic sorbent to extract and concentrate phthalates from water samples. The PPy-coated Fe(3)O(4) magnetic microspheres had the advantages of large surface area, convenient and fast separation ability. The PPy coating of magnetic microspheres contributed to preconcentration of phthalates from water sample, due to the π-π bonding between PPy coating and the analytes. Also, the coating could prevent aggregation of the microspheres, and improve their dispersibility. In this study, seven kinds of phthalates were selected as model analytes, including dimethyl phthalate (DMP), diethyl phthalate (DEP), di-iso-butyl phthalate (DIBP), di-n-butyl phthalate (DBP), benzylbutyl phthalate (BBP), di-(2-ethylhexyl) phthalate (DEHP) and di-n-octyl phthalate (DNOP), and gas chromatography-mass spectrometry (GC-MS) was introduced to detect the phthalates after sample pretreatment. Important parameters of the extraction procedure were investigated, and optimized including eluting solvent, the amount of Fe(3)O(4)@PPy particles, and extraction time. After optimization, the procedure took only 15 min to extract and concentrate analytes with high efficiency. Validation experiments showed that the optimized method had good linearity (0.985-0.998), precision (3.4-11.7%), high recovery (91.1-113.4%), and the limits of detection were from 0.006 to 0.068 μg/L. The results indicated that the novel method had advantages of convenience, good sensitivity, high efficiency, and it could also be applied successfully to analyze phthalates in real water sample.     

Expanding the number of phthalates monitored in house dust

Phthalates have been used as plasticisers for several decades in various industry and consumer products. A method was developed for the determination of 13 not commonly monitored phthalates in household dust. The method was based on solvent extraction using sonication, sample clean-up by solid phase extraction (SPE), and analysis using isotope dilution gas chromatography-tandem mass spectrometry (GC/MS/MS). The method was applied to the analysis of dust samples collected using two vacuum sampling techniques from 38 urban Canadian homes: a sample of fresh or ‘active’ dust (FD) collected by technicians and a composite sample taken from the household vacuum cleaner (HD). Spearman rank correlations between HD and FD samples were significant for six phthalates with median concentrations above their method detection limits (MDLs), suggesting that the HD samples provide comparable results with FD samples. Seven phthalates were detected and quantified in a Canada-wide set of 126 household dust samples, among which six phthalates were detected at frequencies higher than 87%, with median (range) concentrations of 1.9 (<0.42–240) (μg/g) for diisohexyl phthalate (DIHxP), 3.8 (<0.16–260) (μg/g) for di-n-heptyl phthalate (DHepP), 6.6 (<1.1–1170) (μg/g) for diisooctyl phthalate (DIOP), 1.1 (<0.12–390) (μg/g) for di-n-octyl phthalate (DOP), 6.3 (<0.16–430) (μg/g) for dinonyl phthalate (DNP), and 1.8 (<0.18–850) (μg/g) for di-n-decyl phthalate (DDP). High detection frequencies and widely scattered concentration levels of these phthalates in this preliminary set of 126 samples suggested a high variability in potential exposure to phthalates in Canadian homes. NIST SRM 2585 (organic contaminants in house dust) was also analysed; eight phthalates were detected, with concentrations ranging from 6.0 μg/g for DOP to 79 μg/g for DIHxP. The results from SRM 2585 may contribute to the certification of phthalate concentration values in this SRM.     

Determination of adipate plasticizers in poly(vinyl chloride) by microwave-assisted extraction

A new method based on the application of microwave radiation to the extraction of adipate plasticizers from poly(vinyl chloride) PVC plastics is described. The experimental conditions for microwave-assisted extraction (i.e. extracting solvent, temperature, time and microwave power) were evaluated in terms of recovery. The optimisation was carried out with pastes of PVC plastified with di-2-ethylhexyl adipate, and extracts were measured by gas chromatography with flame ionization detection. Six different adipate plasticizers were studied, and microwave-assisted extraction was compared with supercritical fluid extraction for the extraction of adipates and phthalates from PVC matrices. It has been observed that the microwave-assisted extraction parameters evaluated are tightly interconnected. It has been shown that the efficiency of microwave-assisted extraction depends on the kind of solvent, the temperature achieved and the heating time. Moreover, the final temperature reached depends on the microwave power, the number of vessels and the irradiation time. On the other hand, microwave-assisted extraction provides higher recovery values than supercritical fluid extraction for both phthalate and adipate plasticizers.     

Simultaneous determination of seven phthalates and four parabens in cosmetic products using HPLC-DAD and GC-MS methods

Studies on the determination of seven kinds of phthalates, i.e. diethyl phthalate, dipropyl phthalate, dibutyl phthalate, benzyl butyl phthalate, dicyclohexyl phthalate, di-(2-ethylhexyl) phthalate, and dioctyl phthalate, and four parabens, i.e. methylparaben, ethylparaben, propylparaben, and butylparaben, in 15 kinds of cosmetic products, including hair sprays, perfumes, deodorants, cream, lotion, etc., by HPLC with diode array detection and GC-MS in electron impact ionization mode with selected-ion monitoring have been carried out. Methods have been developed for both qualitative and quantitative detection of phthalates and parabens. Extraction, clean-up, and analysis procedures have been optimized. HPLC and GC-MS determinations were performed after sonication-assisted extraction with methanol and clean-up with C18 SPE. These techniques permit detection of phthalates at a level of 10.0-100.0 microg/kg and of parabens at a level of 20.0-200.0 microg/kg. Overall recoveries were 85-108% with RSD values of 4.2-8.8%. Only one of the 15 examined samples was free from phthalates and parabens. The remaining 14 samples were found to contain at least three or more of these phthalates and/or parabens. The predominant phthalates and parabens detected in the studied samples were methylparaben, propylparaben, diethyl phthalate, dibutyl phthalate, dicyclohexyl phthalate, and di-(2-ethylhexyl) phthalate. The residue level is at 1.22-5289 mg/kg.