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1.
As the main source of nutrients for the important pollinator honeybee, bee pollen is crucial for the health of the honeybee and the agro-ecosystem. In the present study, a new sample preparation procedure has been developed for the determination of neonicotinoid pesticides in bee pollen. The neonicotinoid pesticides were extracted using miniaturized salting-out assisted liquid-liquid extraction (mini-SALLE), followed by disposable pipette extraction (DPX) for the clean-up of analytes. Effects of DPX parameters on the clean-up performance were systematically investigated, including sorbent types (PSA, C18, and silica gel), mass of sorbent, loading modes, and elution conditions. In addition, the clean-up effect of classical dispersive solid-phase extraction (d-SPE) was compared with that of the DPX method. Results indicated that PSA-based DPX showed excellent clean-up ability for the high performance liquid chromatography (HPLC) analysis of neonicotinoid pesticides in bee pollen. The proposed DPX method was fully validated and demonstrated to provide the advantage of simple and rapid clean-up with low consumption of solvent. This is the first report of DPX method applied in bee pollen matrix, and would be valuable for the development of a fast sample preparation method for this challenging and important matrix.  相似文献   

2.
In the present work, a high-throughput field sample preparation method was reported for the simultaneous determination of 5-hydroxymethylfurfural and phenolic compounds in honey. Combining a simple and green homogenous liquid–liquid extraction, matrix-induced sugaring-out, with the use of a 96-deepwell plate and multichannel pipette, the proposed method showed its merits in instrument-free and high-throughput preparation. Due to the high-throughput property, the parameters of the method were rapidly and systematically studied using a constructed 4 × 2 × 4 × 3 array (sample amount × ratio of ACN:H2O × standing time × replicates) in a 96-deepwell plate. Analytical performance was fully validated, and the limits of detection and limits of quantification were in the range of 0.17–1.35 μg/g and 0.51–4.14 μg/g, respectively. Recoveries were between 83.98 and 117.11%, and all the precisions were <5%. Furthermore, the developed method was successfully applied in the outdoor preparation of commercial honey samples and the in-field preparation of raw honey samples in apiary. The current work presented a simple, rapid, and high-throughput method for the field sample preparation of honey and provides a valuable strategy for the design of field and on-site sample preparation.  相似文献   

3.
采用基体固相扩散和固相萃取结合的方法提取并净化动物肝脏组织中残留的己烯雌酚,用N-甲基,N-三甲基硅烷三氟乙酰胺衍生化,毛细管气相色谱-质谱联用(选择离子模式,选择离子为:383、397、412、413)对衍生物检测分析,确立了对动物肝脏组织中己烯雌酚定性、定量分析的方法。该法检出限低于1μg/kg;不同DES加入量的回收率为81.6%-100.9%;相对标准偏差8.7%-13.2%。  相似文献   

4.
基质固相分散液相色谱法检测辣椒产品中的黄曲霉毒素   总被引:4,自引:1,他引:4  
郑屏  盛旋  余晓峰  胡艳云 《色谱》2006,24(1):62-64
建立了中性氧化铝-石墨化碳黑的基质固相分散共柱提取净化前处理和以溴为衍生试剂的液相色谱-柱后在线衍生荧光检测法,并将该方法用于辣椒产品中黄曲霉毒素B1,B2,G1,G2的分析。对固相分散剂及共柱净化剂进行了选择和优化。该方法对B1,B2,G1,G2的平均回收率分别为95.4%,87.3%,91.5%和92.6%;方法对B1,G1的检出限为0.25 ng/g,对B2,G2的检出限为0.10 ng/g;对B1,B2,G1,G2进行测定的相对标准偏差(RSD)分别为3.3%,5.8%,4.7%和6.1%。对基质固相分散法和免疫亲和柱法的净化效果进行了比较,结果表明基质固相分散提取净化可以作为一种有效的方法用于辣椒产品中黄曲霉毒素的测定。  相似文献   

5.
基质固相分散-气相色谱/质谱法测定蔬菜中的邻苯二甲酸酯   总被引:13,自引:0,他引:13  
王明林  寇立娟  张玉倩  史衍玺 《色谱》2007,25(4):577-580
利用基质固相分散-气相色谱/质谱法测定了蔬菜中的邻苯二甲酸二甲酯、邻苯二甲酸二乙酯、邻苯二甲酸二丁酯、邻苯二甲酸丁基苄基酯和邻苯二甲酸二异辛酯。蔬菜样品经弗罗里硅土和石墨化炭黑研磨均匀后,用乙酸乙酯淋洗净化,结果表明:上述5种邻苯二甲酸酯在0.05~10.00 mg/L 范围内具有良好的线性,样品的添加回收率为76%~90%,相对标准偏差为2%~7%,5种邻苯二甲酸酯的检出限为0.01~0.024 mg/kg。该方法操作简便、经济,分析速度快,适用于大批量样品的分析。  相似文献   

6.
建立了采用基质分散固相萃取-液相色谱四级杆串联线性离子阱质谱分析罐头食品中双酚类化合物残留的方法.样品中的双酚类化合物残留经0.1%甲酸乙腈提取,基质分散固相萃取净化,外标法定量,液相色谱-质谱测定.使用数据相关采集扫描功能(IDA)结合增强离子产物(EPI)模式对样品中的双酚类进行定性分析,并建立双酚类的二级子离子谱库.通过MRM模式对双酚类进行定量分析,双酚类化合物在4种罐头食品中的平均回收率为49.3%~128.4%(n=6);相对标准偏差在3.2%~14.4%(n-6)之间,可以满足对罐头食品中的双酚类残留的快速同时定性与定量检测的要求.  相似文献   

7.
《Analytical letters》2012,45(7-8):1400-1410
Matrix solid-phase dispersion and gas chromatography-mass spectrometry were used for the rapid screening of 36 pesticides in agricultural products. Homogenized sample (0.5 g), C8-modified silica (0.5 g) and Na2SO4 (1 g) were mixed and transferred to a cartridge containing activated silica (0.5 g). Best recoveries (>60%) were found using dichloromethane-ethyl acetate (4:1) for elution. Analytical characteristics at spiking levels (10–100 μg/kg) were calculated for each pesticide. Matrix effects were studied by comparing the slopes of the matrix-matched calibration curves. Fruit and vegetable samples from South Africa complied with EU and South African current regulation, except for cypermethrin in green beans.  相似文献   

8.
《Analytical letters》2012,45(10):1818-1831
Abstract

A powerful sample cleanup procedure using molecularly imprinted polymer as a solid phase extraction material for the preconcentration of piroxicam in pharmaceutical samples has been developed. The optimized conditions for the preparation of molecularly imprinted polymer as a selective sorbent for the preconcentration of this drug were also studied. It is very important to note that a preconcentration factor of 1000 and retention capacity of 30.0 mg/g can be achieved. Recoveries up to 95% were accomplished for the analyte of interest from a pharmaceutical piroxicam capsule sample. All of these experiments were also performed with nonimprinted polymer.  相似文献   

9.
Obesity is associated with alterations in the composition and amounts of lipids. Lipids have over 1.7 million representatives. Most lipid groups differ in composition, properties and chemical structure. These small molecules control various metabolic pathways, determine the metabolism of other compounds and are substrates for the syntheses of different derivatives. Recently, lipidomics has become an important branch of medical/clinical sciences similar to proteomics and genomics. Due to the much higher lipid accumulation in obese patients and many alterations in the compositions of various groups of lipids, the methods used for sample preparations for lipidomic studies of samples from obese subjects sometimes have to be modified. Appropriate sample preparation methods allow for the identification of a wide range of analytes by advanced analytical methods, including mass spectrometry. This is especially the case in studies with obese subjects, as the amounts of some lipids are much higher, others are present in trace amounts, and obese subjects have some specific alterations of the lipid profile. As a result, it is best to use a method previously tested on samples from obese subjects. However, most of these methods can be also used in healthy, nonobese subjects or patients with other dyslipidemias. This review is an overview of sample preparation methods for analysis as one of the major critical steps in the overall analytical procedure.  相似文献   

10.
A rapid and comprehensive sample preparation method used to extract adriamycin from plasma has been investigated. The samples were passed through an Adsorbex extraction column with an elution solvent. The eluate was directly analyzed by reversed-phase high performance liguid chromatography (HPLC) with fluorescence detector. This solid/liquid extraction method is simpler than the conventional liquid/liquid extraction method. Different elution solvents were used to extract the adriamycin from samples with and without serum. The mobile phase was found to be the optimal elution solvent: 5 mM orthophosphoric acid 62.5% in methanol; acetonitrile; isopropanol = 15:15:7.5, pH 3.2. This method has the merits of better recovery (98%), higher reproducibility, and reguires shorter time and consumes less solvent.  相似文献   

11.
Fabric phase sorptive extraction (FPSE) is an evolutionary sample preparation approach which was introduced in 2014, meeting all green analytical chemistry (GAC) requirements by implementing a natural or synthetic permeable and flexible fabric substrate to host a chemically coated sol–gel organic–inorganic hybrid sorbent in the form of an ultra-thin coating. This construction results in a versatile, fast, and sensitive micro-extraction device. The user-friendly FPSE membrane allows direct extraction of analytes with no sample modification, thus eliminating/minimizing the sample pre-treatment steps, which are not only time consuming, but are also considered the primary source of major analyte loss. Sol–gel sorbent-coated FPSE membranes possess high chemical, solvent, and thermal stability due to the strong covalent bonding between the fabric substrate and the sol–gel sorbent coating. Subsequent to the extraction on FPSE membrane, a wide range of organic solvents can be used in a small volume to exhaustively back-extract the analytes after FPSE process, leading to a high preconcentration factor. In most cases, no solvent evaporation and sample reconstitution are necessary. In addition to the extensive simplification of the sample preparation workflow, FPSE has also innovatively combined the extraction principle of two major, yet competing sample preparation techniques: solid phase extraction (SPE) with its characteristic exhaustive extraction, and solid phase microextraction (SPME) with its characteristic equilibrium driven extraction mechanism. Furthermore, FPSE has offered the most comprehensive cache of sorbent chemistry by successfully combining almost all of the sorbents traditionally used exclusively in either SPE or in SPME. FPSE is the first sample preparation technique to exploit the substrate surface chemistry that complements the overall selectivity and the extraction efficiency of the device. As such, FPSE indeed represents a paradigm shift approach in analytical/bioanalytical sample preparation. Furthermore, an FPSE membrane can be used as an SPME fiber or as an SPE disk for sample preparation, owing to its special geometric advantage. So far, FPSE has overwhelmingly attracted the interest of the separation scientist community, and many analytical scientists have been developing new methodologies by implementing this cutting-edge technique for the extraction and determination of many analytes at their trace and ultra-trace level concentrations in environmental samples as well as in food, pharmaceutical, and biological samples. FPSE offers a total sample preparation solution by providing neutral, cation exchanger, anion exchanger, mixed mode cation exchanger, mixed mode anion exchanger, zwitterionic, and mixed mode zwitterionic sorbents to deal with any analyte regardless of its polarity, ionic state, or the sample matrix where it resides. Herein we present the theoretical background, synthesis, mechanisms of extraction and desorption, the types of sorbents, and the main applications of FPSE so far according to different sample categories, and to briefly show the progress, advantages, and the main principles of the proposed technique.  相似文献   

12.
建立了分散液液微萃取-柱前衍生-高效液相色谱法测定水样中双酚A的分析方法.通过交互正交试验和混合型优化实验设计对影响因素(萃取剂体积、分散剂类型及其体积、水样体积、pH值及离子强度)进行了优化.优化后的分散液液微萃取条件为:60 μL萃取剂,0.4 mL分散剂(甲醇),pH 4.0;优化后的柱前衍生化条件:0.1 mL 2.0 g/L衍生剂(对硝基苯甲酰氯)、衍生化时间30 min;方法的线性范围:0.002~0.2 mg/L(r=0.9997),检出限0.007 μg/L(S/N=3);不同浓度双酚A的萃取率为59.0%~63.0%,相对标准偏差(RSD)2.5%~9.2%(n=5);水样中双酚A的加标率为86.5%~107.1%,RSD为4.0%~11.9%(n=5),其它雌激素(雌酮、雌二醇、雌三醇和17α-乙炔基雌二醇)对双酚A的测定无干扰.本方法可以对水环境中的痕量BPA进行检测,具有操作简便、快速等优点.  相似文献   

13.
Chlorogenic acid (CQA) is one of phenolics commonly found in higher plants, possessing numerous health-promoting effects on humans. Unfortunately, it is easily degraded/transformed into other substances during extraction. Therefore, its reliable analysis requires a special approach that does not involve high temperatures. This paper presents a very simple method of CQA isolation using the sea sand disruption method with subsequent purification of the extract using the ion-pair solid-phase extraction process, followed by HPLC–DAD detection. It was found that control of the ion pairing reagent concentration and sample pH is crucial to improve purification, and that the best results, with recovery exceeding 98%, were obtained for 0.05 M tetrabutylammonium bisulfate at pH 7 when the ion pairs were formed directly in the extract and eluted from the C18 sorbent using an acidified methanol–water mixture. The practical potential of the developed procedure was verified by using it for CQA isolation from different plants. The approach represents one of the contemporary analytical trends and current advances in the solid phase extraction, in which several sorption extraction techniques are combined to ensure high-quality analytical results.  相似文献   

14.
临床样品微量元素分析过程中样品制备技术的进展   总被引:1,自引:0,他引:1  
对临床样品微量元素分析过程中的样品制备技术的最近进展进行了评述,主要从直接稀释、湿法消解、干式灰化及微量元素形态分析的样品预处理技术等几方面进行了分别介绍。  相似文献   

15.
用超临界流体萃取和固相萃取分析水中酚类污染物   总被引:3,自引:0,他引:3  
任丽  王国俊 《分析化学》1997,25(10):1172-1176
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  相似文献   

16.
Sample preparation is an essential step for nearly every type of biochemical analysis in use today. Among the most important of these analyses is the diagnosis of diseases, since their treatment may rely greatly on time and, in the case of infectious diseases, containing their spread within a population to prevent outbreaks. To address this, many different methods have been developed for use in the wide variety of settings for which they are needed. In this work, we have reviewed the literature and report on a broad range of methods that have been developed in recent years and their applications to point-of-care (POC), high-throughput screening, and low-resource and traditional clinical settings for diagnosis, including some of those that were developed in response to the coronavirus disease 2019 (COVID-19) pandemic. In addition to covering alternative approaches and improvements to traditional sample preparation techniques such as extractions and separations, techniques that have been developed with focuses on integration with smart devices, laboratory automation, and biosensors are also discussed.  相似文献   

17.
建立了用弗罗里硅土作基质固相分散剂的加速溶剂萃取、并以灭蚁灵(Mirex)为内标的快速、同时测定土壤中16种有机氯农药的气相色谱法。加速溶剂萃取仪在100℃,10.3Mpa用正己烷和丙酮(1:1,V/V)静态提取样品10min,0.01μg/g加标水平回收率为77.3%-101.3%;方法检出限为0.01—0.04ng/g。方法满足了土壤中有机氯农药残留测定的要求。对我国南方不同地域的72个土壤样品进行了测定,大部分有机氯农药在土壤中都有一定检出量,其中环氧七氯最高(2.6~844.5ng/g),甲氧DDT(23.2—219.8ng/g)和P,P’-DDT(4.0—183.1ng/g)次之,而o,P'-DDT在72个土样中都没有检出。  相似文献   

18.
Pesticides are among the most important contaminants worldwide due to their wide use, persistence, and toxicity. Their presence in soils is not only important from an environmental point of view, but also for food safety issues, since such residues can migrate from soils to food. However, soils are extremely complex matrices, which present a challenge to any analytical chemist, since the extraction of a wide range of compounds with diverse physicochemical properties, such as pesticides, at trace levels is not an easy task. In this context, the QuEChERS method (standing for quick, easy, cheap, effective, rugged, and safe) has become one of the most green and sustainable alternatives in this field due to its inherent advantages, such as fast sample preparation, the minimal use of hazardous reagents and solvents, simplicity, and low cost. This review is aimed at providing a critical revision of the most relevant modifications of the QuEChERS method (including the extraction and clean-up steps of the method) for pesticide-residue analysis in soils.  相似文献   

19.
In this study, ultrasonic assisted miniaturized matrix solid-phase dispersion (US-MMSPD) combined with homogeneous liquid–liquid extraction (HLLE) has been developed as a new method for the extraction of organochlorinated pesticides (OCPs) in fish prior to gas chromatography with electron capture detector (GC-ECD). In the proposed method, OCPs (heptachlor, aldrin, DDE, DDD, lindane and endrin) were first extracted from fish sample into acetonitrile by US-MMSPD procedure, and the extract was then used as consolute solvent in HLLE process. Optimal condition for US-MMSPD step was as follows: volume of acetonitrile, 1.5 mL; temperature of ultrasound, 40 °C; time of ultrasound, 10 min. For HLLE step, optimal results were obtained at the following conditions: volume of chloroform, 35 μL; volume of aqueous phase, 1.5 mL; volume of double distilled water, 0.5 mL; time of centrifuge, 10 min. Under the optimum conditions, the enrichment factors for the studied compounds were obtained in the range of 185–240, and the overall recoveries were ranged from 39.1% to 81.5%. The limits of detection were 0.4–1.2 ng g−1 and the relative standard deviations for 20 ng g−1 of the OCPs, varied from 3.2% to 8% (n = 4). Finally, the proposed method has been successfully applied to the analysis of the OCPs in real fish sample, and satisfactory results were obtained.  相似文献   

20.
Green extraction techniques (GreETs) emerged in the last decade as greener and sustainable alternatives to classical sample preparation procedures aiming to improve the selectivity and sensitivity of analytical methods, simultaneously reducing the deleterious side effects of classical extraction techniques (CETs) for both the operator and the environment. The implementation of improved processes that overcome the main constraints of classical methods in terms of efficiency and ability to minimize or eliminate the use and generation of harmful substances will promote more efficient use of energy and resources in close association with the principles supporting the concept of green chemistry. The current review aims to update the state of the art of some cutting-edge GreETs developed and implemented in recent years focusing on the improvement of the main analytical features, practical aspects, and relevant applications in the biological, food, and environmental fields. Approaches to improve and accelerate the extraction efficiency and to lower solvent consumption, including sorbent-based techniques, such as solid-phase microextraction (SPME) and fabric-phase sorbent extraction (FPSE), and solvent-based techniques (μQuEChERS; micro quick, easy, cheap, effective, rugged, and safe), ultrasound-assisted extraction (UAE), and microwave-assisted extraction (MAE), in addition to supercritical fluid extraction (SFE) and pressurized solvent extraction (PSE), are highlighted.  相似文献   

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