Твердофазна екстракція бензальдегіду і фурфуролу на силікагелі С18, модифікованим 2,4-динітрофенілгідразином і ВЕРХ-УФ визначення в

A variety of popular instant, ground, and brewed coffees were analyzed using a modified liquid chromatography-tandem mass spectrometry (LC-MS/MS) method specifically developed for the determination of acrylamide in foods. Coffee test portions were spiked with 13C3-labeled acrylamide as an internal standard prior to their extraction and cleanup. Ground coffees (1 g) and instant coffees (0.5 g) were extracted by shaking with 9 mL of water for 20 min. Brewed coffee test portions (9 mL) were taken through the cleanup procedure without further dilution with extraction solvent. Coffee test portions were cleaned up by passing 1.5 mL first through an Oasis HLB (hydrophilic/lipophilic copolymer sorbent) solid phase extraction (SPE) cartridge and then a Bond Elut-Accucat (cation and anion exchange sorbent) SPE cartridge. The cleaned up extracts were analyzed by positive ion electrospray LC-MS/MS. The MS/MS data was used to detect, confirm, and quantitate acrylamide. The limit of quantitation of the method was 10 ng/g for ground and instant coffees and 1.0 ng/mL for brewed coffee. The levels of acrylamide ranged from 45 to 374 ng/g in unbrewed coffee grounds, from 172 to 539 ng/g in instant coffee crystals, and from 6 to 16 ng/mL in brewed coffee.

This study used solid phase extraction (SPE) cartridges for rapid cleanup and fractionation of oil samples in oil fingerprinting analysis. A series of commercially available florisil cartridges, normal phase SPE cartridges, and silica gel/cyanopropyl (SiO2/C3-CN) SPE cartridges was selected for the fractionation of oil into aliphatic and aromatic hydrocarbons. The florisil cartridges and normal phase SPE cartridges can clean up the oil samples but are unable to separate them into two fractions. The SiO2/C3-CN (1 g/0.5 g) SPE cartridge successfully separated oil samples into aliphatic and aromatic fractions by eluting with 4 mL of hexane and 4 mL of dichloromethylene (DCM)/hexane (3 : 1, v:v), respectively. No cross-elution was observed between aliphatic and aromatic fractions when oil loading mass was less than 40 mg on the SiO2/C3-CN SPE cartridge. The relative standard deviation (RSD) of five replicates of SPE-GC-MS analysis of 5 mg of reference oil is 2.8%, 1.2%, and 6.9% for total n-alkanes, polycyclic aromatic hydrocarbons (PAHs), and biomarkers, respectively. The recoveries of six spiked deuterated surrogates were all above 95%. This SPE-GC-MS method was used for the fingerprinting analysis of various crude oils, refined petroleum products, and environmental sediment samples. The characterized target hydrocarbons included n-alkanes, unsubstituted priority PAHs and alkylated homologues, and biomarker terpanes and steranes. The concentration profiles and diagnostic ratios of target compounds are both comparable to those obtained by the conventional silica gel column-GC-MS method.

建立了基于通过型固相萃取小柱净化的超高效液相色谱-三重四极杆质谱联用(UPLC-MS/MS)同时快速准确测定牛蛙中9种雌激素(雌三醇(E3)、17β-雌二醇(β-E)、17α-雌二醇(α-E)、17α-炔二雌醇(EE2)、雌酮(EI)、己烯雌酚(DES)、己二烯雌酚(DE)、己烷雌酚(HEX)、醋酸双烯雌酚(DD))残留的检测方法。样品经乙腈提取,经PRiME HLB固相萃取柱净化,Waters Acquity UPLC BEH C18柱(100 mm×2.1 mm, 1.7 μm)分离,以0.5 mmol/L氟化铵水溶液-乙腈体系为流动相梯度洗脱,流速为0.3 mL/min,采用电喷雾正负离子切换模式(ESI+/ESI-)和多反应监测(MRM)扫描方式检测,基质匹配外标法定量分析。该研究优化了液相色谱条件,相比于乙酸铵水溶液-乙腈体系和氨水溶液-乙腈体系,0.5 mmol/L氟化铵水溶液-乙腈体系作为流动相时9种雌激素普遍具有更佳的灵敏度。相比于甲醇和乙酸乙酯,乙腈作为提取溶剂时9种雌激素的提取率提高15%~40%。考察了HLB、C18、Silica、PRiME HLB共4种不同类型的固相萃取小柱的基质净化效应,结果表明,PRiME HLB柱具有更好的基质净化能力。经PRiME HLB净化后,所有化合物的回收率均在70%~125%之间。DD的回收率从47%提高到74%, DES的回收率从180%降低到123%,有效减弱了基质效应。在最佳的实验条件下,E3、β-E、α-E、EI、DE、HEX、DD的线性范围为0.5~100.0 μg/L, EE2和DES的线性范围为1.0~100.0 μg/L, 9种雌激素在各自的线性范围内均有良好的线性关系,相关系数为0.9953~0.9994,方法检出限为0.17~0.33 μg/kg,方法定量限为0.5~1.0 μg/kg,在2.0、10.0、80.0 μg/kg 3个加标水平下,9种雌激素的加标回收率为65.1%~128.2%,相对标准偏差为1.9%~17.6%。该方法操作简便、快速、灵敏,重复性好,可用于大批量样品的同时快速准确检测。

Commercially available solid phase extraction (SPE) cartridges were combined with GC–MS for fast cleanup and fractionation of biodiesel/diesel samples in oil fingerprinting analysis. Several commercially available SPE cartridges (e.g., silica gel/cyanopropyl (SiO2/C3–CN) and extractable petroleum hydrocarbons (EPH) fractionation cartridges), were employed for the fractionation of biodiesel/diesel blends into aliphatic, aromatic hydrocarbons, and fatty acid methyl esters (FAMEs). The SiO2/C3–CN (1 g/0.5 g) SPE cartridge could not separate biodiesel from petroleum hydrocarbons effectively, however, the 5 g EPH SPE cartridge successfully separated blended samples into aliphatic, aromatic and FAME fractions by eluting with 15 mL of hexane, 15 mL of dichloromethylene (DCM)/hexane (1:1, v/v), and 18 mL of DCM, respectively. No cross-elution was observed among aliphatic, aromatic and FAME fractions when the loading mass of blends was less than 8 mg. The relative standard deviations (RSD) for five replicate SPE–GC–MS analyses of 5 mg of diesel blended with 20% biodiesel (volume/volume) and soybean oil ranged from 3.4% to 33.2%, 4.3% to 18.7% and 5.4% to 29.2% for selected alkane, polycyclic aromatic hydrocarbons (PAHs) and FAMEs, respectively. The final recovery rates of surrogates for aliphatic, aromatic and FAME fractions ranged from 82.5 to 91.1%. This developed method was successfully used for the fingerprinting analysis of three simulated blend samples. The concentration profiles of target compounds and the blended level are both comparable to those obtained by the conventional silica gel column–GC–MS method.

Matrix-compatible sorbent coatings based on structurally-tuned polymeric ionic liquids for the determination of acrylamide in brewed coffee and coffee powder using solid-phase microextraction

Rapid solid-phase extraction method to quantify [(11)C]-verapamil, and its [(11)C]-metabolites, in human and macaque plasma.

六氯丁二烯是一种持久性有机污染物,于2015年和2017年分别被列入《斯德哥尔摩公约》附件A和附件C的受控污染物名单中。六氯丁二烯的来源、环境赋存和影响等研究对控制该新增受控持久性有机污染物污染具有重要意义,而灵敏可靠的六氯丁二烯分析方法是开展相关研究的前提和基础。近年来已有不少学者将六氯丁二烯作为分析目标物之一进行了检测或方法学研究。基于这些研究成果,该文综述了六氯丁二烯分析方法的研究进展,其中重点介绍了空气、水体、土壤、污泥、生物组织等多种介质中六氯丁二烯的样品前处理方法,并比较了各方法的优缺点,以期为该领域的进一步研究提供参考。空气中六氯丁二烯主要由泵抽气通过吸附管而采集,再经热脱附后进行仪器分析,检出限在ng/m3水平。也有研究应用聚氨酯泡沫被动采样器和吸附剂填充聚氨酯泡沫被动采样器采集大气中六氯丁二烯及其他污染物。基于吸附剂填充聚氨酯泡沫被动采样器的分析方法灵敏度较高,其对六氯丁二烯的检出限低至0.03 pg/m3。然而目前被动采样体积仅根据六氯丁二烯的log KOA系数估算,未来仍需进一步实验校正。水体样品前处理通常也较简单,通过吹扫捕集、液-液萃取或固相萃取目标物后进行仪器分析。固相萃取法能够同步实现目标物的提取、净化和浓缩,在水样中六氯丁二烯分析方面具有明显优势。固相萃取柱类型以及干燥步骤中柱中残留水分去除率均会影响六氯丁二烯的回收率。灰尘、土壤、沉积物、污泥和生物组织等固体介质样品基质最为复杂,需联合多种方法进行前处理。固体样品中六氯丁二烯提取方法包括索氏提取,加速溶剂萃取和超声萃取,其中超声萃取法应用最为广泛。固体基质净化方面主要采用层析柱色谱法,多根净化柱联用或多层复合柱能够提升净化效果。仪器分析方面,六氯丁二烯主要采用气相色谱和质谱联用检测,高性能质谱检测器如串联质谱能够大大提高六氯丁二烯的检测灵敏度,具有较大的应用潜力。

In this study, simultaneous quantification of allantoin, uric acid, xanthine, and hypoxanthine in cow milk by solid phase extraction (SPE) and high performance liquid chromatography-diode array detection (HPLC-DAD) method was perform. Five different SPE cartridges were tested in order to evaluate the isolation of purine derivatives (PD) from cow milk. Chromatography was carried out on ODS-2 Hypersil column and 0.05 M (NH<sub>4</sub>)<sub>2</sub>HPO<sub>4</sub> buffer solution (pH = 7.76) as mobile phase. The HPLC-DAD validated method showed a linearity with regression coefficients higher than 0.999 and the limits of detection and quantification with values in the range 0.09–0.74 µg mL<sup>–1</sup> and 0.27–2.24 µg mL<sup>–1</sup>, respectively. The method showed good precision with a relative standard deviation (RSD) below 4.48%, while the accuracy ranged from 95.34 to 104.47% for all analytes. The best recovery degree of PD by SPE were obtained on Strata SCX cartridge for xanthine (87.79%) and hypoxanthine (89.02%); on Strata NH<sub>2</sub> for allantoin (35.09%) and on Strata C8 for uric acid (101.08%). Finally, the HPLC-DAD method with SPE on SCX cartridges was applied to quantify the PD in a batch of thirty cow milk samples.

The stability of 24 chemicals, including pharmaceuticals and personal care products, and some agrochemicals on extraction media was evaluated by preloading them onto Oasis hydrophilic lipophilic balanced solid-phase extraction (SPE) cartridges and polar organic chemical integrative samplers (POCIS) followed by storage at -20°C over time. After 20 months, the average loss was 11% on POCIS, with only 2,4-dichlorophenoxyacetic acid, atrazine, chlorpyrifos, and gemfibrozil showing a statistically significant decline compared with initial concentrations. Losses on SPE cartridges were below 19%, with an average loss of 9%. In addition to laboratory spiked samples, multiple POCIS deployed in wastewater-impacted surface waters and SPE extracts of these waters were stored in their original coextracted matrix for nearly two years with minimal observed losses. Errors from typical sampling, handling, and concentration estimates from POCIS sampling rates were typically ± 15 to 30% relative standard deviation, so observed storage losses are minimal for most POCIS applications. While losses during storage on SPE cartridges for 20 months were small but statistically significant for many compounds, addition of labeled internal standards prior to freezing should correct for such losses. Thus, storage of processed water samples for analysis of polar organic pollutants is viable for archival purposes or studies for which samples cannot be analyzed in the short term.

A method for the multiresidue determination of 35 pesticides (30 insecticides and five herbicides) in olive oil by gas chromatography (GC) is described. Three liquid-liquid extraction (LLE) procedures based on (i) partition of pesticides between acetonitrile (ACN) and oil solution in n-hexane, (ii) partition of pesticides between saturated ACN with n-hexane and oil solution in n-hexane saturated with ACN, and (iii) partition of pesticides between ACN and oil were tested for the optimization of the highest pesticide recoveries with the lowest oil residue in the final extracts. Experimental tests were preformed in order to study the efficiency of different clean up procedures with N-Alumina, Florisil, C18, and ENVI-Carb solid-phase extraction (SPE) cartridges for the compounds analyzed by GC-nitrogen phosphorus detection. A second step of clean up was also performed for the compounds analyzed by GC-electron capture detection (ECD), by using phenyl-bonded silica (Ph), diol-bonded silica (Diol), cyanopropyl-bonded silica (CN), and amino propyl-bonded silica (NH2) SPE cartridges. LLE of the oil solution in hexane with ACN followed by an ENVI-Carb SPE clean up of the extract gave the best results for all target compounds. The ACN extract was additionally cleaned through a Diol-SPE cartridge for the determination of pesticides analyzed mainly by GC-ECD. Pesticide recoveries form virgin olive oil spiked with 20, 100, and 500 microg/kg concentrations of pesticides ranged from 70.9 to 107.4%. The proposed method featured good sensitivity, pesticide quantification limits were low enough, and the precision, expressed as relative standard deviation, ranged from 2.4 to 12.0%. The proposed method was applied successfully for the residue determination of the selected pesticides in commercial olive oil samples.

Direct determination of nosiheptide residue in animal tissues by liquid chromatography-tandem mass spectrometry

A method based on accelerated solvent extraction (ASE) coupled with gas chromatography tandem mass spectrometry (GC-MS/MS) was developed for the quantitative analysis of spectinomycin and lincomycin in poultry egg (whole egg, albumen and yolk) samples. In this work, the samples were extracted and purified using an ASE350 instrument and solid-phase extraction (SPE) cartridges, and the parameters of the ASE method were experimentally optimized. The appropriate SPE cartridges were selected, and the conditions for the derivatization reaction were optimized. After derivatization, the poultry egg (whole egg, albumen and yolk) samples were analyzed by GC-MS/MS. This study used blank poultry egg (whole egg, albumen and yolk) samples to evaluate the specificity, sensitivity, linearity, recovery and precision of the method. The linearity (5.6–2000 μg/kg for spectinomycin and 5.9–200 μg/kg for lincomycin), correlation coefficient (≥0.9991), recovery (80.0%–95.7%), precision (relative standard deviations, 1.0%–3.4%), limit of detection (2.3–4.3 μg/kg) and limit of quantification (5.6–9.5 μg/kg) of the method met the requirements for EU parameter verification. Compared with traditional liquid–liquid extraction methods, the proposed method is fast and consumes less reagents, and 24 samples can be processed at a time. Finally, the feasibility of the method was evaluated by testing real samples, and spectinomycin and lincomycin residues in poultry eggs were successfully detected.

An improved solid phase extraction (SPE)-high performance liquid chromatography method was established to determine 15 carbonyl compounds, namely, formaldehyde (FOR), acetaldehyde (ACETA), acrolein (ACR), acetone (ACETO), propionaldehyde (PRO), crotonaldehyde (CRO), butyraldehyde (BUT), benzaldehyde (BEN), isovaleraldehyde (ISO), n-valeraldehyde (VAL), o-methylbenzaldehyde (o-TOL), m-methylbenzaldehyde (m-TOL), p-methylbenzaldehyde (p-TOL), n-hexanal (HEX), and 2,5-dimethylbenzaldehyde (DIM), in soil. The soil was ultrasonically extracted with acetonitrile, and the extracted samples were derivatized with 2,4-dinitrophenylhydrazine (2,4-DNPH) to generate stable hydrazone compounds. The derivatized solutions were cleaned using an SPE cartridge (Welchrom® BRP) packed with N-vinylpyrrolidone/divinylbenzene copolymer. Separation was performed on an Ultimate® XB-C18 column (250 mm×4.6 mm, 5 μm), isocratic elution was performed with acetonitrile-water (65∶35, v/v) as the mobile phase, and detection was performed at a wavelength of 360 nm. The 15 carbonyl compounds in the soil were then quantified using an external standard method. The proposed method improves the sample processing method described in the environmental standard HJ 997-2018: Soil and sediment-Determination of carbonyl compounds-High performance liquid chromatography. A series of experiments revealed the following optimal conditions for soil extraction: acetonitrile as the extraction solvent, extraction temperature of 30 ℃, and extraction time of 10 min. The results showed that the purification effect of the BRP cartridge was significantly better than that of the conventional silica-based C18 cartridge. The 15 carbonyl compounds showed good linearities, and all correlation coefficients were above 0.996. The recoveries ranged from 84.6% to 115.9%, the relative standard deviations (RSDs) ranged from 0.2% to 5.1%, and the detection limits were 0.02-0.06 mg/L. The method is simple, sensitive, and suitable for the accurate quantitative analysis of the 15 carbonyl compounds in soil specified in HJ 997-2018. Thus, the improved method provides reliable technical support for studying the residual status and environmental behavior of carbonyl compounds in soil.

In this paper, a kind of solid phase extraction (SPE) cartridge was prepared using pyrenebutyric acid-bonded silica (PYB) as sorbent. The concentrations of polychlorinated biphenyls (PCBs) in surface water were concentrated by these new SPE cartridges (PYB-SPE) and determined by gas chromatography-mass spectrometry (GC-MS). Some factors including elution solvent, pH, and cartridge burden were investigated in SPE procedures. The results showed that the recoveries of PCBs detected were 70.42-110.51% under optimized conditions. And the performance of PYB-SPE method was similar with the United States Environmental Protection Agency 608 (USEPA608) method and better than C <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">18</sub> -SPE method. The recoveries of PCB congeners determined by PYB-SPE method ranged from 73.9-96.5% in real spiked water samples which were identified to be in accordance with USEPA608 method. The developed PYB-SPE method was successfully applied to the determination of PCBs in water samples.

식품 중 HCAs을 검출하기 위한 최적 전처리 방법을 확립하기 위해 가열 조리된 돼지고기 패티를 이용하여 서로 다른 4가지 SPE(solid-phase extraction)방법을 비교하였다. 4가지 전처리 방법을 통해 얻은 15가지 HCAs 회수율은 3.0%(방법 A, Tri-P-1)-74.7%(방법A, Tri-P-2)이었다. 그 중 <TEX>$MeA{\alpha}C$</TEX>가 평균적으로 73.4%로 가장 높은 회수율을 보였으며 Tri-MeIQx가 15.2%의 가장 낮은 회수율을 보였다. 4가지 전처리 방법 중 방법A와 방법D가 가장 높은 회수율과 검출빈도를 보였으며 방법B와 방법C는 Harman(14.8%)을 제외하고는 전혀 검출되지 않았고 회수율을 구할 수 없었다 발암 가능 물질인 IQ, <TEX>$A{\alpha}C$</TEX>, <TEX>$MeA{\alpha}C$</TEX>, Glu-P-1, Glu-P-2, MeIQ, MeIQx, PhIP 등을 검출하는 방법에는 방법A(48.7-74.6%)가 4가지 방법 중 가장 유리하다. HCAs는 극성에 따라 polar amines과 less-polar amines으로 구분할 수 있는데 방법A는 less-polar amines검출에 유리하고 방법D는 polar amines검출에 유리하다. 방법A와 방법D의 chromatogram을 비교한 결과 방법A와 방법D 모두 15가지 HCAs가 깨끗하게 분리되었지만 Tri-MeIQx 등을 검출하는데 방법A가 더욱 유리하다. SPE 전처리 방법 및 LC/MS 분석방법에 대한 유효성을 확인하기 위해 LOD(0.2-2.1 ng/mL)와 LOQ(0.8-9.7 ng/mL), 표준 편차(0.2-8.6)를 구하였다. Four different extraction and purification methods were evaluated to determine the heterocyclic amines (HCAs) in fried pork patties. Pork patties were cooked in the teflon-coated electric frying pan at <TEX>$230^{\circ}C$</TEX> for 8 min per side. HCAs in the fried pork patties were extracted and purified using four different solid-phase extraction (SPE) methods and quantitated by LC-MS (API-ESI). Recovery of four different extraction and purification methods was evaluated by comparing the HCAs amounts quantified by the standard addition method. Validation of extraction and purification methods for fried pork patties was determined to establish accurate sample preparation. The recoveries of HCAs from different SPE methods were calculated. The recovery yields were 15.7-68.7% (Polar amine group) and 25.0-74.7% (less-polar amine group) in method A. Method D provided recovery yields ranging from 14.1% to 68.7% in polar amine groups and from 3.0% to 72.3% in less-polar amine groups, respectively. Modified procedures of Method A and D were the most suitable extraction and purification method for HCAs analysis from fried pork patties.