Advancement in the derivatizations of the amino groups with the o-phthaldehyde-thiol and with the 9-fluorenylmethyloxycarbonyl chloride reagents

An overview is presented on the advancement of the two most frequently used derivatization protocols applying the o-phthalaldehyde (OPA)-thiol and the fluorenylmethyloxycarbonyl (FMOC) chloride reagents, prior to the high performance liquid chromatographic analysis of amino acids. This review pays special attention (i) to the blank value, to the composition, to the stability and to the life time of the reagents, (ii) to the optimum pH conditions for the interactions and derivatives’ elutions, (iii) to the characteristics and behavior of those amino acids which might provide more than one derivative correlating with the molar ratios of the reagent to the reactants, and (iv) on the practical applicability of the optimized protocols.