A catalogue of selected derivatization reactions to label molecules in the subnanomolar or nanomolar range for CE and micro-HPLC with LIF detection.

Sensitivity is a major obstacle to biochemists studying complex biological mixtures. Laser-induced fluorescence (LIF) is a very sensitive method that can be used with micro-HPLC (microHPLC) or capillary electrophoresis studies and provides an effective solution to these problems. Derivatization is a very useful tool in LIF detection because it allows for the detection of many compounds and is selective, i.e., one dye will label one chemical function specifically. The major difficulty is choosing a derivatization reaction among the huge number of reactions described in the literature and making it work at a very low level of concentration. Another limitation is the use of a laser wavelength, which can excite the derivatized molecules. This article discusses selected derivatization reactions for labeling molecules in the subnanomolar or nanomolar range for CE and microHPLC. Derivatization for amines, sugars, aldehydes, carboxylic acids, thiols, diols, and nucleotides are described, and derivatization procedures are presented. In many cases, the subnanomolar and nanomolar concentration of these compounds can be detected using these chemical reactions.