Comparison of Solid-Phase Extraction and Liquid-Liquid Extraction Methods for Liquid Chromatographic Determination of Diltiazem and its Metabolites in Plasma

Abstract

A rapid solid-phase extraction method for the determination of diltiazem and its metabolites from plasma was compared to a conventional liquid-liquid extraction procedure we have described previously. Analytical recovery for all compounds was greater than 90 % for solid-phase extraction whereas for liquid-liquid extraction, mean recovery ranged from 67 to 82 %. The increase of extraction efficiency was closely related to an improvement of the detection limit for the metabolites. Solid phase extraction procedure was found to be more convenient, rapid and sensitive than liquid-liquid extraction and represents a useful analytical tool for the monitoring of diltiazem and its metabolites in clinical investigations.     

Solid-Phase Extraction of Carbamazepine and Two Major Metabolites from Plasma for Analysis by HPLC

Abstract

A rapid, sensitive and simple to operate HPLC method for the simultaneous determination of carbamazepine, carbamazepine 10,11-epoxide and 10,11-dihydro-10,11-trans-dihydroxycarbamazepine in plasma is described. The drug and its metabolites are extracted from plasma using commercially available reversed-phase octadecylsilane bonded-silica columns (Bond Elut C₁₈, 2.8 ml capacity). Separation was achieved by reversed-phase chromatography, using a mobile phase consisting of acetonitrile - methanol - water (19:37:44) at a flow-rate of 1.8 ml/min in conjunction with a Waters Assoc. Nova-Pak C₁₈ column. The analytical column, in Radial-Pak cartridge form, was used in combination with a Waters Assoc. Z-module RCSS and protected by a Waters Assoc. Guard-Pak precolumn module containing a Guard-Pak μBondapak C₁₈ insert. Using ultraviolet detection at 214 nm, levels in the region of 50–100 ng/ml for CBZ and its metabolites can be measured with only 250 μl of plasma. The method has been used to determine steady-state concentrations of the drug and its metabolites in paediatric patients.     

Determination of Anthelmintic Pharmaceuticals in Wastewater by Solid-Phase Extraction and Thin-Layer Chromatography

JPC – Journal of Planar Chromatography – Modern TLC - The presented study describes the development, optimization, and validation of a method for the determination of four structurally...     

Automated Solid-Phase Extraction and Liquid Chromatography Tandem Mass Spectrometry Determination of N-methyl-2-pyrrolidone and its Metabolites in Urine and Plasma

A method for the simultaneous determination of N-methyl-2-pyrrolidone (NMP) and its metabolites 5-hydroxyl-N-pyrrolidone (5HNMP), N-methylsuccinimide (MSI) and 2-hydroxy-N-methylsuccinimide (2HMSI) in plasma and urine has been developed. Samples were purified by SPE using an ASPEC XL4. Analysis was performed using LC–MS equipped with an APCI interface. The analysis provided linear responses in the range of 0.125–12 μg mL⁻¹ for all of the analytes and up to 150 μg mL⁻¹ for 5HNMP and 2HMSI. The within day precision was in the range of 0.9–19.1% for plasma samples and 1.9–10.4% for urine samples whereas the between day precisions were 4.5–11.9% and 1.2–17.5%, respectively. The method was deemed to be suitable for monitoring the levels of NMP and its metabolites in the plasma and urine of occupationally exposed persons.     

药毒物分析中磁性固相萃取技术的应用进展

磁性固相萃取是一种新型的样品前处理技术,具有萃取时间短、吸附能力强、有机溶剂使用量少、操作简单快捷等优点,已经广泛应用于样品的分离提纯.在简要介绍磁性固相萃取技术发展、材料制备的基础上,着重对国内外磁性固相萃取技术在药毒物分析方面的发展现状以及应用进展进行了综述,以期为法庭科学领域相关物证鉴定提供参考,为严厉打击相关违法犯罪活动提供科学理论与实践依据.     

Large Volume Headspace Analysis Using Solid-Phase Microcolumn Extraction

A rapid and simple large volume headspace (HS) sampling technique termed headspace solid-phase microcolumn extraction (HS-SPMCE) is described. HS gas above a liquid or solid sample is aspirated by attaching a gas-tight syringe onto a glass thermal desorption tube filled with Tenax sorbent. The trapped analytes are recovered by thermal desorption for gas chromatography–mass spectrometry (GC–MS) analysis. Benzene, toluene, ethylbenzene and the xylene isomers (BTEX) are used as model compounds to demonstrate the application of the extraction procedure for water samples. The results of the tests of the effect of agitation time and aspiration rate on recovery of the analytes show a good robustness of the method. BTEX are determined in the linear range from 0.5 to 50.0 μg L^?1 with limits of detection (3 σ) ranging within 0.09–0.14 μg L^?1 (MS was in scan mode). The method provides a good repeatability (RSD < 9%) and only a negligible carryover effect was observed ( ≤0.05%) when analysing BTEX at concentration 50.0 μg L^?1.     

用超临界流体萃取和固相萃取分析水中酚类污染物

使用自制的超临界流体萃取仪，比较了从Ｃｈｒｏｍｏｓｏｒｂ，Ｐｏｒａｐａｒｋ和ＧＤＸ系列的８种吸附剂上萃取苯酚，邻硝基酚，邻氯酚，对氯酚，对二甲酚，２，４－二氯酚和２，４，６－三氯酚的回收率。并用萃取回收率比较高的ＧＤＸ－３０１富集１Ｌ酸性水样中１０＾－７ｇ／ｍＬ级的以上各酚，然后用超临界ＣＯ２脱附，回收率从３２．５％到９２．９％，同时还对超临界ＣＯ２脱附ＧＤＸ－３０１上各酚的操作条件进行了优化，并     

可卡因及代谢物的分析检测研究进展

综述了近十年来生物检材中可卡因及其代谢物分析常用的样品前处理技术和检测方法,比较了液-液萃取、固相萃取、固相微萃取等提取方法的可行性和局限性及气相色谱、气相色谱-质谱联用、液相色谱-质谱联用等检测方法的应用进展。     

Solid-Phase Extraction and LC with Fluorescence Detection for Analysis of PAHs in Rainwater

The efficiency of extraction of polycyclic aromatic hydrocarbons (PAHs) from rainwater by solid-phase extraction (SPE) with three different types of cartridge, and analysis by high-performance liquid chromatography with fluorescence detection, are discussed in this paper. Three cartridges were investigated but only one was suitable. After equilibration in a desiccator for 65–80 h or in ambient air for 90–100 h the SPE cartridges were activated with 5 mL dichloromethane then 5 mL 2-propanol. The volume of sample passed through the cartridges was 50 mL; after loading of the sample the cartridges were dried under vacuum for approximately 20 min by application of a pressure of 15 mbar to the SPE manifold. The PAHs were eluted with 5 mL dichloromethane–hexane, 50:50 (v/v). The flow rate used for conditioning, sample loading, and elution was 2.5 mL min⁻¹, achieved by application of a pressure of 6 mbar. For analysis of PAHs in rainwater, recovery was between 67 and 99%, the relative standard deviation varied between 2 and 5%, and the detection limits of the method were less than 16.9 ng L⁻¹ for several PAHs. These optimum conditions were used for analysis of rainwater collected between June 2002 and May 2003 at two sites in Alsace (eastern France) and 17 PAHs were quantitatively determined. Concentrations varied between 1.6 and 968.1 ng L⁻¹.     

固相萃取-高效液相色谱法测定蔬菜水果中的氨基甲酸酯杀虫剂及其代谢物残留

采用乙腈提取-固相萃取浓缩 高效液相色谱分离 柱后衍生-荧光检测法测定了蔬菜 水果中8种氨基甲酸酯类杀虫剂及其代谢物残留量。采用加标法(添加水平为0.10,0.50mg/kg)测定了氨基甲酸酯杀虫剂及其代谢物的回收率,其平均回收率为70%-120%,相对标准偏差(RSD)小于20%(n=3),最低检出限范围为0.0042-0.0106 mg/kg。该方法的测定结果满足多残留农残的检测要求。     

Analysis of Mepivacaine in Human Serum by Gas Chromatography After Solid-Phase Extraction

A method using solid-phase extraction (SPE) has been developed for analysis of mepivacaine in human serum. A procedure for isolation of mepivacaine and lidocaine (internal standard) from human serum by use of Chromosorb 104 (acrylonitrile–divinylbenzene polymer) as extraction adsorbent is described in detail. Analysis was performed by gas chromatography on an HP-INNOWax (cross-linked PEG) capillary column, with flame ionization detection, after splitless injection. Relative standard deviations ranged between 3.6 and 4.4 for a serum mepivacaine concentration of 0.5 g mL^–1 and between 4.7 and 5.9 for a concentration of 1 g mL^–1. Recoveries were approximately 95%. The method was applied in a stomatological clinic to healthy volunteers to whom anesthesia with mepivacaine was administered.     

Analysis of Organic Pollutants in Surface Water by Solid-Phase Extraction and Gas Chromatograph-Mass Spectrometry

Solid-phase extraction (SPE) is an emerging chromatographic sample preparation technique. The novel extraction technique can reduce the time and volume of organic solvents required, and alleviate problems associated with the formation of emulsions as compared to conventional liquid-liquid extractions. This study was designed to apply SPE vacuum manifold to determine organic pollutants in surface water of Huan River binding with GC-MSD system.     

超声辅助提取-固相萃取土壤中头孢菌素C的高效液相色谱法定量检测

建立了一种采用超声辅助提取(UAE)、强阴离子交换固相萃取(SAX-SPE)净化、高效液相色谱(HPLC)测定土壤中残留头孢菌素C(CPC)简单、快速方法。 样品以超纯水为提取剂,超声辅助提取,SPE柱子以3 mL甲醇和3 mL水活化,采用5 mL的10%甲醇水溶液作为淋洗液,2 mL的5%甲酸水溶液/甲醇溶液(体积比50：50)进行洗脱,高效液相色谱紫外检测器(HPLC-PDA)测定,检测波长λ=254 nm,柱温30 ℃ ,流动相为0.1%甲酸水溶液/甲醇溶液(体积比95：5)对土壤中不同加标浓度的CPC进行检测,方法的回收率在77.9%~98.9%,标准偏差范围为5.0%~6.3%(n=5),方法检出限(LOD)为340.4 μg/kg,定量限(LOQ)为1126.8 μg/kg。 同时采用此方法检测分析新疆某药厂附近阳性土壤样品,不同批次土壤样品结果分别为:检出(低于定量限)、1532.1 μg/kg。     

Matrix Solid-Phase Dispersion Extraction for Analysis of Cypermethrin Residue in Cows’ Milk

A method of extraction based on matrix solid-phase dispersion has been developed, optimized, and validated by chromatographic analysis of cypermethrin pesticide residues in samples of cows’ milk. Milk (0.25 g) was fortified with cypermethrin and blended with 1 g each of C₁₈ (octadecylsilane) silica and Na₂SO₄ (anhydrous sodium sulfate), used to trap fats and water, respectively. The homogenized material was transferred to a commercial SPE cartridge containing 1 g activated Florisil with 5 mL acetonitrile. Cypermethrin was eluted under vacuum with 5 × 2 mL acetonitrile and the extract was concentrated to 1 mL and analyzed by gas chromatography–mass spectrometry. The limits of detection and quantification of the method were 0.025 and 0.08 mg kg⁻¹, respectively.

     

Solid-Phase Extraction of Trace Amounts of Selenomethionine

Abstract

Preconcentration and separation of trace amounts of selenomethionine was investigated using several solid sorbents. The best results were obtained with copper-treated Chelex 100 chelating resin. Selenomethionine from 100 ml of solution adsorbed on 0.2 g of the resin was eluted with 8 ml of 1.5 mol/l ammonia solution and determined by electrothermal atomic absorption spectrometry. The column chromatography with Cu-Chelex and functionalized cellulose sorbent Cellex T was applied to separate organic and inorganic selenium forms.     

固相萃取-气相色谱-质谱法测定土壤中阿特拉津

应用固相萃取-气相色谱-质谱法测定土壤中阿特拉津的含量。土壤样品采用索氏提取,硅胶固相萃取小柱净化。在气相色谱分离中用TR-5MS色谱柱为固定相,在质谱分析中采用选择离子检测模式。阿特拉津的质量浓度在5.00~200μg·L-1范围内与其峰面积呈线性关系,检出限为0.32ng·g-1。加标回收率在88.2%~90.7%之间,测定值的相对标准偏差(n=10)为4.8%。     

固相微萃取法和液液萃取K-D浓缩法对化妆品香气的分析

分别利用固相微萃取法和液液萃取K-D浓缩法对化妆品调理水中的香气提取物进行分析比较。用这两种方法从化妆品调理水中提取、鉴定出30个化合物,从固相微萃取法提取物中鉴定出23个化合物,液液萃取K-D浓缩法提取物中鉴定出16个化合物,其中相同的化合物有9个。结果表明,两种提取方法得到的香气成分有明显差异,其香气特征成分主要集中在固相微萃取法所富集部分,因此采用固相微萃取法能够快速、高效、全面地对香气的香型进行定性分析。     

HPLC Analysis of Cefmetazole and Nocardicins A and E in Human Serum and Urine Using Solid-Phase Extraction

Abstract

A method for extraction and quantification of cefmetazole and nocardicins A and E in serum and urine samples is described in this paper. Sample pretreatment is carried out using solid-phase extraction cartridges, resulting in very high extraction recoveries of these β-lactam antibiotics. The procedure, which prepares biological fluids for reversed-phase high-performance liquid chromatographic analysis is convenient, rapid and reproducible. An water-methanol-acetic acid mobile phase was used with benzotriazole as an internal standard. The detection limit was 0.2 μg/ml at 280 nm.     

固相萃取-气相色谱质谱联用法测定蔬菜中杜烯残留

建立固相萃取-气相色谱-质谱联用内标法测定蔬菜中杜烯残留量的检测方法.样品经乙腈提取,弗罗里硅土固相柱净化后,用气相色谱质谱联用仪进行检测.方法的检出限为0.005 mg/kg,经过不同实验室验证,样品中杜烯的平均基体添加回收率在81.0%～112.0%之间,室间精密度在1.03%～3.89%之间.     

SPE-GC/MS法检测人血中的鸦片类毒品

采用混合型强阳离子固相萃取柱（SPE）对血液中的吗啡、可待因、6-单乙酰吗啡3种鸦片类毒品进行提取,提取液吹干后,再用N-甲基-双三氟乙酰胺（MBTFA）衍生化,进行GC/MS-SIM检测。以乙基吗啡为内标,3种毒品检测的线性相关系数均大于0.99, 线性范围为10~1000μg/L,相对回收率分别为90%~116 %、90%~110%、79%~102 % ;日内和日间相对标准偏差分别小于10%和16%;检测限分别为1、0.5和3 μg/L。该方法灵敏度高、重现性好、操作简便,可用于鸦片类毒品滥用者或中毒者血液中的毒品及其代谢物的检测。