固相萃取–超高效液相色谱三重四级杆质谱联用法测定水中四环素、土霉素及罗红霉素

建立了固相萃取–超高效液相色谱三重四级杆质谱联用法同时测定水中的罗红霉素、四环素和土霉素残留。水样经过固相萃取纯化、富集,液质联用分析,采用甲酸溶液和乙腈作为流动相,在5 min内完成对3种目标化合物的分析,3种目标化合物的方法检出限介于0.08~0.35 ng/L之间,测定结果的相对标准偏差为1.4%~5.6%,空白样品和实际样品的加标回收率分别为82.5%~114%,71.5%~126%。     

固相萃取/超高效液相色谱法测定龙胆泻肝丸中栀子苷、龙胆苦苷与黄芩苷

建立了一种快速测定龙胆泻肝丸中栀子苷、龙胆苦苷和黄芩苷3种有效成分的超高效液相色谱方法。样品经50%甲醇提取,C18固相萃取(SPE)小柱净化后,采用Ultimate XB-C18色谱柱(4.6 mm×50 mm,1.8μm)进行分离,以乙腈-0.1%磷酸溶液为流动相进行梯度洗脱。考察了不同规格色谱柱、流动相梯度比例、进样体积、柱温和流速对分离效果的影响,并对SPE柱流出液的平衡体积进一步考察,在最佳分析条件下进行液相色谱分析,该方法显示了良好的线性关系(r≥0.999 8),其定量下限(LOQ)为0.24～0.44 mg/L,加标回收率为95%～99%。该方法快速、准确,可满足实际检测需要。     

Development and optimization of the determination of pharmaceuticals in water samples by SPE and HPLC with diode‐array detection

This paper describes the development, optimization, and validation of a method for the determination of five pharmaceuticals from different therapeutic classes (antibiotics, anthelmintics, glucocorticoides) in water samples. Water samples were prepared using SPE and extracts were analyzed by HPLC with diode‐array detection. The efficiency of 11 different SPE cartridges to extract the investigated compounds from water was tested in preliminary experiments. Then, the pH of the water sample, elution solvent, and sorbent mass were optimized. Except for optimization of the SPE procedure, selection of the optimal HPLC column with different stationary phases from different manufacturers has been performed. The developed method was validated using spring water samples spiked with appropriate concentrations of pharmaceuticals. Good linearity was obtained in the range of 2.4–200 μg/L, depending on the pharmaceutical with the correlation coefficients >0.9930 in all cases, except for ciprofloxacin (0.9866). Also, the method has revealed that low LODs (0.7–3.9 μg/L), good precision (intra‐ and interday) with RSD below 17% and recoveries above 98% for all pharmaceuticals. The method has been successfully applied to the analysis of production wastewater samples from the pharmaceutical industry.     

Comparison of different sample pre‐treatments for multi‐residue analysis of organochlorine and pyrethroid pesticides in chrysanthemum by gas chromatography with electron capture detection

The widespread use of insecticides in Chinese herbal medicines has created a compelling need for the development of a multiresidue analytical method to help assure herbs safety. The operating variables affecting the performance of the multiresidue analysis of 34 organochlorine and 12 pyrethroid pesticides in chrysanthemum, a widely used kind of Chinese herbal medicines, were evaluated. Three different extraction solvents including n‐hexane and its mixtures with acetone and petroleum ether were compared, and n‐hexane was found to be an appropriate option. A combination of gel permeation chromatography and SPE was selected as the optimum cleanup, in comparison with dispersive SPE, or the two former methods alone. The determination of the 46 pesticide residues in the spiked chrysanthemum samples was performed by GC with electron capture detection. The average recoveries ranged from 71.3 to 102.6% with RSDs of 1.4–15.7% for all of the pesticides. The LOQs were in the range of 0.0015–0.2 mg/kg, while the LODs were between 0.0005 and 0.1 mg/kg. The satisfactory accuracy, and precision, in combination with a good separation and few interferences, have demonstrated the strong potential of this technique for its application in chrysanthemum analysis.     

Analysis of Polar Thermally Labile Pesticides using Different Solid-Phase Extraction (SPE) Materials with GC and HPLC Techniques

Abstract

In the present study, an efficient method for extraction, separation and determination of a limited number (30) of polar pesticides in aqueous matrices has been developed. Pesticides were extracted with high recoveries (usually >85%) from 1 L water samples, using the solid-phase extraction (SPE) technique. Affinities to different SPE materials (C-18 and XAD resins) have been studied for all pesticides. Special attention has been paid to the following 5 pesticides (which have classified by the EC as compounds which are particularly difficult to analyse): benazolia, bromofenoxim, ethofumesate, fenamiphos and phenmediphain. Thermally labile compounds have been determined with high pressure liquid chromatography (HPLC) and UV detection in comparison to TSP-LC-MS. Absolute limits of detection (LODs) for the HPLC technique are usually below 1 ng at 220 nm. Thermospray LC-MS determination shows usually limits of detection of 1-10 ng (SCAN) and 60-800 pg (SIM). All pesticides, which are amenable to GC have been detected in a comparative study with the following detectors: flame ionization detector (FID), nitrogen-phosphorus detector (NPD), electron capture detector (ECD) and atomic emission detector (AED). Element-specific detection of various functional groups of these pesticides has been achieved using GC-AED. Thus, while the FID has the lowest specificity, the AED is the most specific detector. LODs are usually < 300 pg (FID < 20 pg, NPD < 1 pg, ECD < 1 pg, AED < 300 pg). Spiked river water samples (from the River Leine and River Weser in Lower Saxony, Germany) have been used to test the employed method. With the spiked surface water samples recoveries were usually >80%.     

Solid-phase extraction clean-up procedure for the analysis of PAHs in lichens

A clean-up procedure based on a solid-phase extraction column was optimized for determination of polycyclic aromatic hydrocarbons (PAHs) in lichen extracts to remove co-extracted compounds from the matrix in the final extract. Several kinds of solid phases were evaluated: normal phase (-NH₂ and alumina), strong anion exchange and reversed phase. The -NH₂ columns were the most effective by using a packed solid bed of 500?mg. The lichen raw extract was loaded on the column previously conditioned with dichloromethane and hexane. Hexane (0.5?mL) was used as rinsing solvent, and PAHs were quantitatively eluted (80–97%) using 2?mL of hexane–dichloromethane (65–35) as eluting solvent. In these conditions, even the heaviest PAHs were quantitatively eluted. The optimized SPE method provides a short time and low-solvent-consumption sample clean-up compared with other conventional methods based on column chromatography. The analytical procedure, dynamic sonication-assisted extraction, followed by the optimized solid-phase extraction clean-up, was used to determine the 16 EPA priority PAHs from native lichens collected from the Aragon valley in central Pyrenees. The PAH concentrations in lichen samples ranged from 352 to 1654?ng?g^?1, and the minimum concentration value was established as the regional reference PAH levels in the area.     

An evaluation of antifouling booster biocides in Gran Canaria coastal waters using SPE-LC MS/MS

A solid phase extraction (SPE) technique for seawater samples coupled to quantification using liquid chromatography tandem-mass spectrometry (LC-MS/MS) is described to quantify relevant antifouling booster biocides of ecotoxicological concern (Diuron, TCMTB, Irgarol 1051 and Dichlofluanid). The optimised methodology provides a sensitive, easy to use and efficient analytical procedure with detection limits in the range of between 0.1 and 0.2?ng?L^?1 and appropriate reproducibility (with analytical standard deviations of less than 10%). Spiked recoveries for all compounds exceeded 72%. The method was tested through a thorough monitoring regime of commercial port and marinas on the island of Gran Canaria (off the north-west coast of Africa) over a period of several months in 2008. Results provide the first data for antifouling booster biocides in the Canary Islands. Concentrations of Diuron and Irgarol 1051 in samples ranged between 2 and 195?ng?L^?1 and 2 and 146?ng?L^?1, respectively. TCMTB and Dichlofluanid were not detected.     

Determination of 61 organic pollutants in drinking water by solid phase extraction followed by liquid and gas chromatography coupled to tandem mass spectrometry: an analytical strategy for a routine laboratory

A method for determination of 61 organic pollutants (polycyclic aromatic hydrocarbons and organochlorine, organophosphorous and organonitrogen pesticides) is proposed. It is based on solid phase extraction (SPE) and subsequent analysis of the extract by liquid and gas chromatography coupled to tandem mass spectrometry. Method validation yielded to the following values: limits of quantification, from 0.005 to 0.020?µg?L^?1; trueness, 95% to 113% and reproducibility (as percent relative standard deviation), 2% to 15%. Additionally, the method performed well in various proficiency tests.     

柱切换液相色谱法快速定量检测参附注射液中乌头碱类生物碱和人参皂苷

利用柱切换液相色谱,建立了参附注射液中苯甲酰新乌头原碱、苯甲酰乌头原碱、苯甲酰次乌头原碱、新乌头碱、次乌头碱和乌头碱6种乌头碱类生物碱,以及Rg1、Re、Rf、Rb1、Rc、Ro、Rb2、Rb3、Rd 9种人参皂苷的分析方法。首先利用强阳离子交换的在线固相小柱选择性富集和净化样品中生物碱类成分,优化了色谱条件;并采用EC－C18柱作为人参皂苷的分析柱,通过优化实验条件,结合柱切换方式,去除了样品中辅料等大极性基质成分对色谱柱的污染,实现了生物碱分析和人参皂苷分析的自动切换。结果显示,样品中的生物碱和人参皂苷分离良好,线性相关系数（r2）均大于0.999,连续进样精密度的相对标准偏差（RSD） < 2.0%,重复性的RSD < 2.0%;其中6种生物碱的平均回收率为95.1%～98.6%,检出限为4.0～8.2 ng/mL;9种人参皂苷的平均回收率为91.7%～104%。所构建的基于柱切换液相色谱技术的在线固相萃取方法能够有效去除样品中的基质干扰,快速完成参附注射液中3种单酯型生物碱和9种人参皂苷的快速定量,同时也可对3种双酯型生物碱进行限量检测,可应用于药物的质量评价。