Carboxylic acids (CAs) represent a large group of important molecules participating in various biologically significant processes. Analytical study of these compounds is typically performed by liquid chromatography (LC) combined with various types of detection. However, their analysis is often accompanied by a wide variety of problems depending on used separation system or detection method. The dominant ones are: i) poor chromatographic behavior of the CAs in reversed-phase LC; ii) absence of a chromophore (or fluorophore); iii) weak ionization in mass spectrometry (MS). To overcome these problems, targeted chemical modification, and derivatization, come into play. Therefore, derivatization still plays an important and, in many cases, irreplaceable role in sample preparation, and new derivatization methods of CAs are constantly being developed. The most commonly used type of reaction for CAs derivatization is amidation. In recent years, an increased interest in the isotopic labeling derivatization method has been observed. In this review, we comprehensively summarize the possibilities and actual trends in the derivatization of CAs that have been published over the past decade.

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LC 分析前羧基的衍生化 – 综述

羧酸（CA）代表一大类参与各种具有重要生物学意义的过程的重要分子。这些化合物的分析研究通常通过液相色谱 (LC) 结合各种类型的检测来进行。然而，根据所使用的分离系统或检测方法，它们的分析常常伴随着各种各样的问题。主要问题是： i) CA 在反相 LC 中的色谱行为较差； ii) 不存在发色团（或荧光团）； iii) 质谱 (MS) 中的弱电离。为了克服这些问题，有针对性的化学修饰和衍生化开始发挥作用。因此，衍生化在样品制备中仍然发挥着重要且在许多情况下不可替代的作用，并且新的CA衍生方法正在不断开发。 CA 衍生化最常用的反应类型是酰胺化。近年来，人们对同位素标记衍生化方法的兴趣日益浓厚。在这篇综述中，我们全面总结了过去十年已发表的CA衍生化的可能性和实际趋势。