Benramdane L, Bressolle F, Vallon J J
Laboratoire de Biochimie, Pharmacotoxicologie et Analyse des traces, Hôpital E. Herriot, Lyon, France.
J Chromatogr Sci. 1999 Sep;37(9):330-44. doi: 10.1093/chromsci/37.9.330.
Although acute intoxication has become rare, arsenic (As) is still a dangerous pollution agent for industrial workers and people living in the vicinity of emission sources. In humans, only inorganic As is toxic; organic forms present in large amounts in the environment are nontoxic. It is therefore important to be able to differentiate one group from the other using appropriate speciation methods. The authors review the present knowledge of the distribution of As in humans and food products. The three steps of the speciation methods (sample preparation, species separation, and detection) are described. For liquid samples, a clean-up step (C18 cartridge extraction, dilution, or freezing) is necessary to eliminate proteins and salts from the matrix. For solid organic samples, the first step consists of the digestion of tissues followed by solvent extraction sometimes coupled with a C18 extraction. The separation of As species is accomplished by different high-performance liquid chromatography (HPLC) methods (ion-exchange, ion-pairing, and micellar liquid chromatography). The detection methods are compatible with HPLC and are able to detect As species in the microgram-per-liter range. Inductively coupled plasma (ICP) atomic emission spectrometry is more frequently used, but suffers from interference by organic solvents in the mobile phases. Atomic absorption spectrometry methods give sensitivities of the same order. ICP-mass spectrometry has the advantage of specificity and can be 100- to 1000-fold more sensitive than previous methods.
尽管急性中毒已变得罕见，但砷（As）对于产业工人以及生活在排放源附近的人们而言，仍然是一种危险的污染剂。在人类体内，只有无机砷具有毒性；环境中大量存在的有机形式则无毒。因此，运用适当的形态分析方法区分这两类砷很重要。作者回顾了目前关于砷在人体和食品中分布的知识。描述了形态分析方法的三个步骤（样品制备、物种分离和检测）。对于液体样品，需要一个净化步骤（C18柱萃取、稀释或冷冻）以去除基质中的蛋白质和盐分。对于固体有机样品，第一步是组织消化，随后有时会进行溶剂萃取并结合C18萃取。砷物种的分离通过不同的高效液相色谱（HPLC）方法（离子交换、离子对和胶束液相色谱）来完成。检测方法与HPLC兼容，能够检测微克每升范围内的砷物种。电感耦合等离子体（ICP）原子发射光谱法使用得更为频繁，但会受到流动相中有机溶剂的干扰。原子吸收光谱法的灵敏度相当。ICP质谱法具有特异性优势，灵敏度可比先前方法高100至1000倍。
