3.38 - Advances in Sample Preparation of Environmental Solid Matrices

Abstract

Sample treatment is perhaps the most critical step in analysis and thus the most demanding area of analytical procedures. Solid samples almost always require extraction steps and it is in this area that novel and advanced techniques have been developed. This chapter contains a short description and literature review of the most novel sample treatment techniques for this task, including supercritical fluid extraction, pressurized liquid extraction, microwave-assisted extraction, ultrasound-assisted extraction, hyphenation, and miniaturization of techniques. In each case, the basic concepts on which the techniques are based, their advantages and drawbacks, and some applications are described. The relevant information on the analytes, techniques, and experimental procedures are included in two tables, to help the reader to select the most appropriate technique and make decisions about them. The data are based on more than 400 scientific references dealing with the subject. This is not an exhaustive list of techniques, matrices, and applications, but much useful information is provided. Common problems related to the matrix composition, hyphenated techniques for sample preparation, and versatility of the devices are discussed to give some ideas about new approaches. References are limited to 50, but the content corresponds to a much wider overview.