共查询到20条相似文献,搜索用时 62 毫秒
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脂质作为细胞膜和亚细胞膜的主要结构成分,在能量来源、细胞信号传导等多种生物学过程中发挥着重要作用。近年来,脂质分析受到越来越多的关注,其中色谱-质谱联用技术在脂质分析中占据主导地位。由于样品基质复杂,样品前处理有富集痕量物质和减少基质干扰的作用,成为脂质分析中的一个关键步骤。该文综述了近年来基于色谱-质谱联用技术的脂质分析中样品前处理技术的研究进展和应用,对各种样品前处理技术进行了阐述和总结。基于液相的萃取方法有液-液萃取和单一有机溶剂萃取。基于固相的萃取方法包括固相萃取和固相微萃取。场辅助萃取方法包括超临界流体萃取、加压流体萃取、微波辅助萃取和超声辅助萃取。此外,还介绍了在线联用样品前处理方法和用于活体分析的样品前处理方法。最后,对基于色谱-质谱联用的脂质分析样品前处理技术存在的问题及发展趋势进行了探讨。样品前处理技术的发展将提高脂质分析的灵敏度、选择性和分析速度。 相似文献
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文中对固相微萃取,作为一种试样预处理的新技术,在1990-2004年的进展作了评述,介绍了固相微萃取技术的装置、试验方法、原理、涂层、影响因素、应用及发展趋势,引用文献39篇。 相似文献
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样品制备与处理的进展——无溶剂萃取技术 总被引:12,自引:0,他引:12
本文讨论了现代分析化学的重要领域之一, 样品制备及前处理技术的进展--无溶剂萃取技术。包括气相萃取、超临界流体萃取、膜萃取、固相萃取、固相微萃取等方法。简述了这些方法的原理及其应用, 探讨了样品制备与前处理技术的发展动向。 相似文献
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采用微波辅助提取(MAE)与液相色谱-串联质谱(LC-MS/MS)技术,建立了同时测定人体指甲中14种抗精神失常及安眠镇静类物质的分析方法。指甲经冷冻研磨后加入内标溶液,用微波辅助提取。以Allure PFPP苯基柱分离,甲醇(含20 mmol/L乙酸铵)-乙酸铵(20 mmol/L)进行梯度洗脱,采用二级质谱多反应监测模式(MRM)检测14种抗精神失常和安眠镇静类物质及其代谢物。目标物在对应含量范围内均线性良好(r~2≥0.990);检出限为0.1~50 pg/mg;大多数目标物的定量下限为100 pg/mg;日内精密度和日间精密度均不大于7.8%;准确度在±10.16%范围内。对7例服用部分抗精神失常及安眠镇静类药物的患者指甲进行分析,目标物检出情况与用药情况相符。该方法样品处理简便、高效、快速且分析准确、灵敏度高、选择性好,可用于人体指甲中pg/mg级抗精神失常及安眠镇静类物质的定性定量分析。 相似文献
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微波萃取土壤中PAHs的研究 总被引:33,自引:0,他引:33
研究了MK-1型光纤压力自控微波溶样系统用于微波萃取的可行性.以合成土样为对象,比较系统地研究了微波萃取PAHs的条件、萃取效率以及溶剂、水分、土壤基体物质等因素的影响.在微波作用下丙酮-正已烷(体积比为1:1)和二氯甲烷对PAHs的萃取能力相近;试样中小于20%的水分使丙酮-正己烷(体积比为1:1)的萃取能力提高,而水分高于5%则使二氯甲烷的萃取能力略有降低.在选定条件下,萘、苊烯、芴、菲、蒽、(出)、苯并(a)芘的回收率在82.2%~94.1%之间. 相似文献
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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
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LIMin-jing YOUJing-yan YAOShuang DINGLan LIUZhong-ying ZHANGHan-qi 《高等学校化学研究》2004,20(6):703-706
Three microwave-assisted extraction(MAE) procedures were studied. The first procedure was household microwave oven dynamic extraction(HMODE). The second procedure was special microwave oven bath extraction (SMOBE). The third procedure was microwave resonant cavity dynamic extraction (MRCDE). The results obtained by the three microwave-assisted extraction procedures were compared with those obtained by using traditional Soxhlet extraction. The results indicate that the MAE not only took a shorter time, but also simplified the procedure, and made the extraction a higher yield. At the same time the results obtained by the three MAE procedures were also compared with each other. 相似文献
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密闭微波辅助萃取丹参中有效成分的研究 总被引:17,自引:2,他引:17
应用具有压力控制附件的MSP-100D密闭微波萃取装置,对丹参中的有效成分丹参酮、丹参酮A及隐丹参酮进行微波萃取研究.在乙醇体积分数为90%,微波辐射时间为4min,溶剂体积对样品质量比为20∶1和样品粒径为120目的条件下,有效成分提取率最佳.对比了密闭微波萃取同索氏萃取和超声萃取丹参有效成分的差异. 相似文献
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建立了微波辅助-微固相在线萃取/气相色谱-质谱联用(GC-MS)测定污泥中19种多氯联苯(PCBs)含量的分析方法。对微波辅助-微固相在线萃取条件进行优化,得出最优萃取条件为:萃取温度60℃,萃取时间25 min,解吸溶剂为乙酸乙酯,解吸剂用量150μL,解吸时间25 min。在优化条件下,方法的检出限为0.2~2.5 ng/g,相对标准偏差(RSD)小于14%,回收率为81.4%~102.1%。与传统的微波萃取、微固相萃取、超声萃取等方法相比,该方法集萃取、净化和浓缩于一体,极大地缩短了分析时间,适合于复杂环境样品体系中痕量PCBs的分析检测。 相似文献
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Fiber-in-Tube Solid Phase Extraction (FIT-SPE) for Miniaturized Sample Preparation Process 总被引:2,自引:0,他引:2
A typical analytical separation procedure has several important steps: sample preparation, isolation, identification, quantitation, statistical evaluation and final decision. Each step is alwayscritical to obtain correct results to fulfill the analytical purpose. In these various steps sample 相似文献
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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