食品安全日益受到重视,食品检测意义重大。食物基质很复杂,并且已经确定了各种食物危害。因此,食品基质的检测方法和样品制备技术必须不断优化和更新。当色谱系统用于确定食品危害时,通常需要几个步骤:样品制备,也就是说,使用合适的预处理方法和目标物质分离和纯化从不同的底物中分离目标,这通常使用色谱分离来实现。用于定性和定量分析的适当检测器的选择通常基于目标化合物的性质。样品制备过程被认为是整个食品分析过程中最耗时的方面。它也容易出现分析错误。因此,样品制备过程的优化是化学分析领域的一个关键问题。研究人员开发了一系列新的,高效,和准确的样品预处理方法,在线样品制备系统已被发现是一种可行的方法。与液相色谱-质谱联用(LC-MS)的在线样品制备具有许多优点。首先,手动操作可以减少分析误差,以确保良好的准确性和可重复性。它还可以减少化学试剂的消耗并避免样品之间的交叉污染。此外,在线样品制备系统可以缩短样品制备时间,提高检测效率。LC-MS联用技术在环境领域得到了广泛的应用,生物学和食物。与LC-MS耦合的在线样品制备系统分为两个模块:第一模块涉及样品制备,第二模块涉及LC系统。第一模块去除杂质并分离目标化合物以准备它们的定性和定量检测。这两个模块的耦合主要取决于阀门切换。在本文中,我们介绍了最常用的在线样品制备技术,包括在线固相萃取(在线SPE),管内固相微萃取(管内SPME),和湍流色谱(TFC)。然后,我们详细介绍了这三种在线分析技术的基本原理和耦合设备。耦合设备在两个模块之间建立物理连接。接下来,我们讨论了在线样品制备柱中不同净化填料的性能。农药残留在线系统的应用及研究进展,兽药残留,和生物毒素也进行了讨论。与离线样品制备相比,在线分析系统具有几个优点。在线分析系统不仅可以大大减少分析时间和溶剂消耗,而且可以提高检测的灵敏度和准确性。此类系统可用于确定食品危害以确保食品安全。最后,对在线分析系统存在的问题和发展趋势进行了探讨和展望。促进在线分析技术在食品安全检测中的应用,我们建议考虑以下三个方面。首先,更多带有新型填料的在线纯化柱,除了C18或聚合物填料,应该开发。第二,与普通探测器相比,高分辨率MS检测器具有更好的精度和准确性。将在线分析技术与高分辨率质谱仪耦合可能有利于在线分析的进一步发展。第三,应比较和评估不同的食品基质,以不断优化检测过程并提高在线分析系统的效率。随着人们对食品安全问题的关注增加,预计在线分析技术在食品检测中的应用将变得越来越重要。
Food safety has received increased attention, and food detection is of great significance. The food matrix is complex, and diverse food hazards have been identified. Thus, the detection methods and sample preparation techniques for food matrices must be continuously optimized and updated. Several steps are usually required when a chromatographic system is used to determine food hazards: sample preparation, that is, the separation of targets from different substrates using a suitable preprocessing method and target-substance separation and purification, which is usually achieved using chromatographic separation. The selection of an appropriate detector for qualitative and quantitative analyses is usually based on the properties of the target compound. The sample preparation procedure is considered the most time-consuming aspect of the entire food-analysis process. It is also prone to analytical errors. Therefore, optimization of the sample preparation process is a key issue in the field of chemical analysis. Researchers have developed a series of new, efficient, and accurate sample preprocessing methods, and an on-line sample-preparation system has been found to be a feasible approach. On-line sample preparation coupled with liquid chromatography-mass spectrometry (LC-MS) presents many advantages. First, manual operation could reduce analytical errors to ensure good accuracy and repeatability. It could also reduce the consumption of chemical reagents and avoid cross-contamination between samples. Furthermore, an on-line sample-preparation system could shorten the sample-preparation time and improve the detection efficiency. On-line sample preparation coupled with LC-MS has been widely applied in the fields of environment, biology, and food. On-line sample preparation systems coupled with LC-MS are divided into two modules: the first modules involves sample preparation and the second module involves the LC system. The first module remove impurities and isolates the target compounds in preparation for their qualitative and quantitative detection. The coupling of these two modules depends mainly on valve switching. In this paper, we introduce the most frequently used on-line sample-preparation techniques, including on-line solid phase extraction (on-line SPE), in-tube solid phase microextraction (in-tube SPME), and turbulent chromatography (TFC). We then describe the basic principles and coupling equipment of these three on-line analytical technologies in detail. The coupling equipment establishes a physical connection between the two modules. Next, we discuss the properties of different purification fillers in an on-line sample-preparation column. The applications and research progress of on-line systems for pesticide residues, veterinary drug residues, and biotoxins are also discussed. Compared with offline sample preparation, on-line analytical systems present several advantages. On-line analytical systems can not only greatly reduce the analysis time and solvent consumption but also improve the detection sensitivity and accuracy. Such systems can be used to determine food hazards to ensure food safety. Finally, the existing problems and development trends of on-line analytical systems are discussed and prospected. To promote the applications of on-line analytical technology in food-safety detection, we suggest that the following three aspects be considered. First, more on-line purification columns with novel fillers, in addition to C18 or polymer fillers, should be developed. Second, compared with ordinary detectors, high-resolution MS detectors have better precision and accuracy. Coupling on-line analytical technologies with a high-resolution mass spectrometer may be beneficial for the further development of on-line analyses. Third, different food matrices should be compared and evaluated to continuously optimize the detection process and improve the efficiency of on-line analytical systems. As concerns regarding food safety issues have increased, the applications of on-line analytical technologies for food detection can be expected to become increasingly important.