Naphtalene-2,3-Dicarbaldehyde Derivatization Of Amino Acids - An Improved Technique For Minimization Of Benzoin Condensation

The capillary electrophoresis coupled with fluorescence detection is a very powerful tool for analysis of amino acids in biological samples such as urine, plasma, liquor, etc. It can be also used for an additional diagnosis of various metabolic disorders. Labelling with fluorophore molecule is necessary in order to detect amino acids (AA) with a fluorescence detector. For this purpose various derivatization techniques have been introduced over the years. Naphtalene-2,3-dicarbaldehyde (NDA) reaction with a primary amine group in the presence of a cyanide ion is often used to form fluorescent 2-substituted 1-cyanobenz[f]insodoles. Nevertheless, to the best of our knowledge, no unified method was described in research publications. In this study, various mixing schemes were tested to propose the best technique for the derivatization reaction in high yield and reproducibility.