Chapter 5 Application of nitroalkanes and secondary retention index standards for the identification of drugs

Publisher Summary This chapter discusses applications of nitroalkanes and secondary retention index standards for the identification of drugs. High-performance liquid chromatography (HPLC) offers some specific qualities that assure its place among other chromatographic methods relevant to toxicological screening analysis and make it a method of choice for the analysis of conjugated drug metabolites. The separation potential of HPLC is much higher and the detection limits much lower than those of less sophisticated thin layer chromatography (TLC). Moreover, HPLC may be applied to non-volatile, thermolabile, and highly polar substances. Reversed-phase column packings have been more frequently applied for toxicological screening than straight phase silica. Most often, octadecyl- or octyl-silica is used as the column packing and a mixture of methanol or acetonitrile with an acidic buffer, containing an amine modifier, as the mobile phase. The prerequisite for the efficient use of any retention index scale for compound identification is the robustness of the individual retention index (RI)-values of the compounds stored in a given database.