tailieunhanh - Drugs and Poisons in Humans - A Handbook of Practical Analysis (Part 4)

Introduction: Small amount of drugs and poisons incorporated into human bodies are hidden among large amounts of biological components, such as proteins, lipids, nucleic acids and membranes. It is not easy to detect only a target compound from such complicated matrices. Before instrumental analysis, extraction procedure is usually essential and very important. Extraction methods are used for removal of such proteins and lipids existing in large amounts in biological matrices, for removal of impurity compounds interfering with chromatographic separation, for condensation of a target compound, and for removal of compounds causing troubles (such as obstruction of chromatographic columns and contamination. | Pretreatments of human specimens By Akira Namera and Mikio Yashiki Introduction Small amount of drugs and poisons incorporated into human bodies are hidden among large amounts of biological components such as proteins lipids nucleic acids and membranes. It is not easy to detect only a target compound from such complicated matrices. Before instrumental analysis extraction procedure is usually essential and very important. Extraction methods are used for removal of such proteins and lipids existing in large amounts in biological matrices for removal of impurity compounds interfering with chromatographic separation for condensation of a target compound and for removal of compounds causing troubles such as obstruction of chromatographic columns and contamination of a detector in instrumental analysis. There are numerous methods of extraction according to target compounds. In this chapter the authors briefly present some pretreatment methods including extraction and derivatization usually being used in biomedical analysis. Many reviews and books on the details of extractions are available 1-5 . Extraction methods According to the advancement of analytical instruments there are some reports on the analysis of compounds using crude biological samples without any tedious extraction procedure or with dilution with water only this is solely dependent upon the high capability of an instrument. However in view of the stability and tool life it is desirable to make suitable pretreatments. In emergency medicine where a long time for analysis is not permitted a rapid extraction method with the minimal purification step is chosen to meet such demand. For extraction of polar or ionic compounds a biological specimen can be acidified with tartaric acid followed by addition of acetone or ethanol shaking of the mixture and centrifugation. To extract metals organic compounds in a biological specimen should be completely destroyed dry or wet incineration methods are employed. For the