Newer Approaches to the Isolation, Identification, and Quantitation of Steroids in Biological Materials

Abstract

Publisher Summary This chapter discusses the newer approaches to the isolation, identification, and quantitation of steroids in biological materials. Progress in steroid analysis has been remarkable in the last 15 years. Much of present knowledge in steroid endocrinology could not have been acquired without the development of radioimmunoassay and other competitive protein-binding methods. These methods have provided the sensitivity and speed required for measurement of physiological concentrations of steroid hormones in large series of samples. Parallel with this development, both liquid and gas-liquid chromatographic methods have been markedly improved and mass spectrometers have become available for routine use. The most important advancement in this area has been the successful combination of gas chromatography and mass spectrometry (GC-MS) for analysis of molecules as large as steroids. Immunoassay and GC-MS are complementary methods. GC-MS is important as a reference method to test and validate the specificity of an immunoassay. The steroid composition of biological samples taken under different physiological and pathological conditions can be characterized by GC-MS, and immunoassays may then be developed for detailed studies of selected steroids in larger numbers of samples.