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1.
通过采电电感耦合等离子发射光谱对10种法国小麦样品、2种中国小麦样品、7种法国小麦面粉样品以及4种中国面粉样品进行了钙、镁、锌、铁、锰、铜、钼、钾及磷共9种微和常量元素的含量分析.结果表明:小麦样品中元素含量最高的为磷、钾和镁,其次为钙、铁、锌、锰、铜和钼.小麦面粉样品中元素含量最高的为磷、钾、钙和镁,其次为铁、锌、锰、铜和钼.法国小麦样品中的1号样品(TREMIE)是居第一位的含微量元素量较高的小麦品种,中国小麦面粉样品的11号样品(标粉)是居第一位含微量元素较高的小麦面粉样品.其中对人体有益的元素远远不能满足人体的需要.  相似文献   

2.
叙述了一种定量分析岩石中微量元素的火花源质谱法。大约10~25毫克绝缘粉末样品直接压在T型电极上。在选定的分析条件下进行单曝光摄谱。用AGV—1做标准样品,计算相对灵敏度因子。此方法可分析24个元素。相对标准偏差为±20%。做了地幔和月岩等样品分析。  相似文献   

3.
水产品含有丰富的蛋白、维生素和多种微量元素,是人们摄取动物性蛋白质的重要来源之一,我国是世界上最大的水产品消费国,其质量安全问题一直备受关注。但水产样品基质复杂,有害物质的含量低,须对其进行分离富集后才能进行检测,传统的液-液萃取、固相萃取和快速固相分散萃取等样品前处理技术在水产品分析中得到广泛应用,同时针对一些挥发性和超痕量有害物质检测时,固相微萃取同样体现出巨大优势。这些样品前处理技术可以有效去除基体对分析对象的干扰,提高检测方法的灵敏度和准确度。根据目标分析物性质的不同,选择合适的样品前处理技术,是水产品中有害物质分析的关键步骤。该文以水产品中有害物的来源不同,将其分为3类:(1)水产品中环境污染物的分析;(2)养殖运输和加工过程中有害物的分析;(3)水产品中生物毒素的分析。以这3类有害物质的分析为主线,综述了近10年水产品中有害物质分析的样品前处理技术,包括液-液萃取、固相萃取、固相微萃取、快速固相分散萃取和磁性固相萃取等。此外,还对各种技术的优缺点进行了探讨,并对其未来发展方向进行了展望。  相似文献   

4.
采用了微波等离子体发射光谱仪,针对地质矿石类样品进行了多种主量和微量元素的快速分析,验证了方法的检出限,准确度以及相关一致性。结果表明,采用Agilent 4100 MP-AES分析一系列地质样品效果良好,与传统原子吸收光谱法(AAS)相比,操作简便成本低,安全性更高,适合此类地质样品的分析。  相似文献   

5.
质谱技术具有灵敏度高、分析速度快、能提供分子结构信息等特点,在生命科学研究领域扮演着重要角色,常用于组织样品分析。传统地,组织样品分析一般需经过研磨、萃取、分离等繁杂的预处理过程,导致耗时低效,无法满足大量样品高通量分析的实际需求,且不可避免地使组织样品中的一些活性成分损失。近年来,随着新型常压质谱技术的发展,使得组织样品可在无需样品预处理的条件下进行实时、非破坏、在线直接质谱分析,大大提高了分析效率。该文着重介绍了新型直接质谱技术在组织样品分析中的应用,并简要展望了该技术在生命科学、临床医学、食品科学、活体分析等领域的发展趋势。  相似文献   

6.
采用质谱、核磁、红外及紫外对河豚毒素样品进行结构确证,采用柱后衍生高效液相荧光法对该纯度标准样品进行定值并进行了均匀性、稳定性检验。标准样品经国内6个具有分析资质的实验室进行协同定值,定值结果为99.45%,其扩展不确定度(95%置信区间)为0.51%。该标准样品达到国家标准样品的技术要求,可用于有关河豚毒素的方法校正和质量控制。  相似文献   

7.
电感耦合等离子体发射光谱法(ICP-AES)应用于土壤及环境样品的分析,多有报道。我们用HClO_4-HNO_3-HF混酸分解土壤样品,利用元素间干扰系数法修正土壤样品中基体元素对微量元素测定的干扰,测定了土壤标准参考物质中16种元素,其测定结果均能满足欲测元素定值要求。  相似文献   

8.
复杂样品质谱分析技术的原理与应用   总被引:11,自引:1,他引:10  
原位、实时、在线、非破坏、高通量、低耗损的质谱学方法是质谱分析技术发展的重要趋势.在无需样品预处理的条件下对复杂基体样品中痕量待测物直接离子化技术的出现,极大地提高了质谱分析的效率,使实际样品的快速质谱分析成为可能.本文着重综述了能够在无需样品预处理情况下对复杂基体样品离子化的新兴质谱技术及其应用研究,系统阐述了直接离子化技术的基本原理和方法,介绍了几种典型的常压直接离子化技术和装置,对直接离子化质谱分析技术在食品、药品、环境、活体分析、代谢组学、蛋白质组学以及生物组织质谱成像等领域的典型应用进行了述评,讨论了提高复杂样品快速质谱分析选择性的可能方法,并展望了常压直接离子化技术未来发展的可能趋势.  相似文献   

9.
摘要对西安市某辖区妇幼保健站及多家幼儿园920名2~6岁身体健康儿童的全血样品进行微量元素检测,统计得到该区域正常儿童微量元素的含量范围,为准确了解西安地区某区域2-6岁正常儿童体内微量元素正常含量提供了参考数据。  相似文献   

10.
感耦等离子体发射光谱法(ICP-AES)在土壤、地质和环境样品的分析中已有广泛应用。由于直读ICP光谱仪有很好的测量精度,因此常量元素分析的精度和准确度在很大程度上取决于样品的化学前处理,我们用HCIO_4-HNO_3-HF混酸分解沉积物样品,几种常量元素测定的变异系数小于2%,本工作用这种方法分解取自西藏的土壤标准参考样品,七种常量元素的测定结果均很好地满足标样元素定值要求。影响微量元素准确测定的因素较多,基体元素的干扰是主要因素之一。本工作在原有工作的基础上,进一步研究了样品中主要基体元素对微量元素测定的光谱干扰,讨论了利用元素间干扰系数法进行光谱干扰修正所遇到的一些问题。  相似文献   

11.
Ultra high performance liquid chromatography and supercritical fluid chromatography techniques are favored because of their high efficiency and fast analysis speed. Although many sample preparation techniques have been coupled with common liquid chromatography online, the online coupling of sample preparation with the two popular chromatography techniques have gained increasing attention owing to the increasing requirements of efficiency and sensitivity. In this review, we have discussed and summarized the recent advances of the online coupling of sample preparation with ultra high performance liquid chromatography and supercritical fluid chromatography techniques. The main sample preparation techniques that have been coupled with ultra high performance liquid chromatography online are solid‐phase extraction and in‐tube solid‐phase microextraction, while solid‐phase extraction and supercritical fluid extraction are the main techniques that have been coupled with supercritical fluid chromatography online. Especially, the strategies for online coupling of sample preparation with chromatography techniques were summarized. Typical applications and growing trends of the online coupling techniques were also discussed in detail. With the increasing demands of improving the efficiency, throughput, and analytical capability toward complex samples of the analysis methods, online coupling of sample preparation with chromatography techniques will acquire further development.  相似文献   

12.
杨吉娜  刘丹阳  周婷 《色谱》2020,38(1):74-85
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   

13.
Sample preparation turns out to be one of the important procedures in complex sample analysis by affecting the accuracy, selectivity, and sensitivity of analytical results. However, the majority of the conventional sample preparation techniques still suffer from time-consuming and labor-intensive operations. These shortcomings can be addressed by reforming the sample preparation process in a microfluidic manner. Inheriting the advantages of rapid, high efficiency, low consumption, and easy integration, microfluidic sample preparation techniques receive increasing attention, including microfluidic phases separation, microfluidic field-assisted extraction, microfluidic membrane separation, and microfluidic chemical conversion. This review overviews the progress of microfluidic sample preparation techniques in the last 3 years based on more than 100 references, we highlight the implementation of typical sample preparation methods in the formats of microfluidics. Furthermore, the challenges and outlooks of the application of microfluidic sample preparation techniques are discussed.  相似文献   

14.
The determination of trace residues and contaminants in complex matrices, such as food, often requires extensive sample extraction and preparation prior to instrumental analysis. Sample preparation is often the bottleneck in analysis and there is a need to minimise the number of steps to reduce both time and sources of error. There is also a move towards more environmentally friendly techniques, which use less solvent and smaller sample sizes. Smaller sample size becomes important when dealing with real life problems, such as consumer complaints and alleged chemical contamination. Optimal sample preparation can reduce analysis time, sources of error, enhance sensitivity and enable unequivocal identification, confirmation and quantification. This review considers all aspects of sample preparation, covering general extraction techniques, such as Soxhlet and pressurised liquid extraction, microextraction techniques such as liquid phase microextraction (LPME) and more selective techniques, such as solid phase extraction (SPE), solid phase microextraction (SPME) and stir bar sorptive extraction (SBSE). The applicability of each technique in food analysis, particularly for the determination of trace organic contaminants in foods is discussed.  相似文献   

15.
刘玉兰  陈雅莉  肖小华  夏凌  李攻科 《色谱》2020,38(10):1197-1205
样品前处理能将待测物从复杂基质中预先分离富集出来,以提高分析方法的灵敏度、选择性和准确性,是复杂样品分析的关键步骤。样品前处理是一个非自发的、从无序到有序的熵减过程,不仅费时费力,还极易引起误差。向体系输入能量和降低体系熵值可以增强分离富集效果,加快样品制备过程。将电场引入在线样品前处理,既能向体系做功,又能驱动样品定向迁移,使前处理的熵减过程快速顺利进行,是快速样品制备的有效途径。基于电驱动的在线分离富集技术综合了多种加速策略:(1)以电场形式向体系输入能量,加速传质和传热过程;(2)采用电渗流、电泳等电驱动定向流实现样品在分离、富集、检测各步骤之间的定向迁移,保证样品前处理与检测顺利进行;(3)利用在线联用技术集成样品前处理与分析检测各步骤,从而提高自动化程度,减少人为误差;(4)通过微型化装置或微萃取方法提高样品制备效率,缩短样品制备时间。该文总结了近10年与基于电驱动的在线快速分离富集技术相关的90多篇文献,综述了该技术领域的研究进展,探讨了电驱动毛细管在线快速分离富集技术、电驱动芯片在线快速分离富集技术和电驱动膜萃取在线分离富集技术各自的优势和潜力,并展望了该类技术的发展与应用趋势。  相似文献   

16.
Sample preparation before chromatographic separation is the most time-consuming and error-prone part of the analytical procedure. Therefore, selecting and optimizing an appropriate sample preparation scheme is a key factor in the final success of the analysis, and the judicious choice of an appropriate procedure greatly influences the reliability and accuracy of a given analysis. The main objective of this review is to critically evaluate the applicability, disadvantages, and advantages of various sample preparation techniques. Particular emphasis is placed on extraction techniques suitable for both liquid and solid samples. Figure Miniaturised extraction techniques allow sensitive analysis of also small sample volumes.  相似文献   

17.
Sample preparation is the procedure before instrumental analysis and significant to its effectiveness and efficiency. However, this procedure is usually time‐consuming, labor intensive, and prone to error. In the last decade, the development of sample preparation techniques has received increasing attention, especially in complex sample application. To pretreat samples faster and more effectively, advanced materials, instrumentation, and methods have been combined with typical techniques, including extraction, membrane separation, and chemical conversion techniques. Researchers in China focused on the development of simple, efficient sample preparation methods with selective enrichment and rapid separation capabilities for target analysis in complicated sample matrix and contribute almost a half of the publications in this specific field. In this review, a panorama of sample preparation techniques in China has been composed from more than 140 references, and we highlight some promising methods developed during recent years and introduce different separation materials with respect to these methods.  相似文献   

18.
Miniaturized sample preparation methods designed as the sample pretreatment for liquid phase separations, such as liquid chromatography, capillary electrophoresis and capillary electrochromatography, have been reviewed especially for the on-line coupling of the sample preparation process and the separation process. The development of the desorption interfaces for the effective combining of the sample preparation and subsequent liquid phase separations is briefly described along with the applications of the combined analytical systems to the analysis of complex sample mixtures such as biological and environmental matrices. Novel use of fine polymeric filaments as the extraction medium for microscale liquid phase separation methods are investigated and a comparison is made with other sample preparation techniques. Polymer coating onto the fibrous material is also introduced to further develop microscale sample preparation methods with improved extraction performance. Several other microscale sample preparation methods having a potential compatibility to the liquid phase separations are also described for future applications of these techniques.  相似文献   

19.
Microextraction-based sample preparation techniques have exhibited remarkable importance in analytical chemistry since they were first developed in the 1980s. The application of these techniques involves efficient and, at the same time, environmentally-friendly analytical methodologies. They are also generally faster when compared with classical sample preparation techniques, requiring low solvent and sample volumes, and also allowing for automated or semi-automated procedures. This paper provides an overview of the basic principles of sample preparation techniques and the important applications and developments that have taken place in this area over the past five years. These procedures include solid-phase microextraction (SPME), stir bar sorptive extraction (SBSE), bar adsorptive microextraction (BAμE), rotating disk sorptive extraction (RDSE), micro solid-phase extraction (μ-SPE) and liquid-phase microextraction (LPME). The main variations are discussed with a focus on recent applications in the analysis of environmental water samples. Lastly, some of the trends and perspectives associated with these outstanding microextraction sample preparation approaches are highlighted.  相似文献   

20.
Sample preparation and introduction techniques are very critical steps in gas chromatography analysis and particularly in the analysis of volatiles in solid samples. In these cases, they can be divided into two main categories: direct and indirect approaches, based on how the solid sample is treated, i.e. with and without dissolution (or extraction) of analytes from the solid sample. To enable routine application, coupling with sample preparation techniques (especially solid or solvent‐based microextractions) is needed to achieve automation. Here, an overview of the most common sample introduction techniques for gas chromatography with their advantages and drawbacks is presented and discussed, including references to relevant examples. So, this review can serve as guidance for new users.  相似文献   

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