Institute of Chemistry, University of Campinas (UNICAMP), P.O. Box 6154, 13083-970, Campinas, SP, Brazil.
Environmental Studies Center (CEA), São Paulo State University (UNESP), Avenida 24-A, 1515, Rio Claro, SP, 13506-900, Brazil.
Talanta. 2021 May 1;226:122119. doi: 10.1016/j.talanta.2021.122119. Epub 2021 Jan 17.
Chemical speciation is a relevant topic in environmental chemistry since the (eco)toxicity, bio (geo)chemical cycles, and mobility of a given element depend on its chemical forms (oxidation state, organic ligands, etc.). Maintaining the chemical stability of the species and avoiding equilibrium disruptions during the sample treatment is one of the biggest challenges in chemical speciation, especially in environmental matrices where the level of concomitants/interferents is normally high. To achieve this task, strategies based on chemical properties of the species can be carried out and pre-concentration techniques are often needed due to the low concentration ranges of many species (μg L - ng L). Due to the significance of the topic and the lack of reviews dealing with sample preparation of metal (loid)s (usually, sample preparation reviews focus on the total metal content), this work is presented. This review gives an up-to-date overview of the most common sample preparation techniques for environmental samples (water, soil, and sediments), with a focus on speciation of metal/metalloids and determination by spectrometric techniques. Description of the methods is given, and the most recent applications (last 10 years) are presented.
化学形态分析是环境化学中的一个重要课题，因为给定元素的（生态）毒性、生物（地球）化学循环和迁移性取决于其化学形态（氧化态、有机配体等）。在化学形态分析中，保持物种的化学稳定性并避免在样品处理过程中平衡破坏是最大的挑战之一，特别是在共存物/干扰物水平通常较高的环境基质中。为了实现这一任务，可以基于物种的化学性质来进行策略，并由于许多物种的浓度范围较低（μg L-ng L），因此通常需要预浓缩技术。由于该主题的重要性以及缺乏涉及金属（类）样品制备的综述（通常，样品制备综述侧重于总金属含量），因此提出了这项工作。本综述对环境样品（水、土壤和沉积物）中最常见的样品制备技术进行了最新的概述，重点是金属/类金属的形态分析和光谱技术的测定。介绍了这些方法，并呈现了最新的应用（过去 10 年）。
