No abstract

SummaryWe report four new derivatization agents, acridone-N-acetic acid (ARC), carbazole-9-ylacetic acid (CRA), carbazole-9-ylpropionic acid (CRP), and 2-methyl-2-carbazole-9-ylacetic acid (MCRA), with strong fluorescence emission which has low dependence on solvent polarity. The emission maxima for ARC, CRA, CRP, and MCRA were 430 nm ()~ex 404 nm), 368 nm ()~ex 335 nm), 356 nm ()~ex 340 nm) and 360 nm @ex 330 nm), respectively. The effects of mobile-phase composition, pH, and temperature on the liquid chromatographic retention behavior of the four fluorescence agents were investigated. An experimental model was established for calculating the inclusion constants of cyclodextrin (CD) complexes in the dynamic state, using [3-cyclodextrin (~-CD) and hydroxypropyl-[~-cyclodextrin (HP-~-CD) as examples, and different mobilephase compositions. On the basis of the model, the inclusion constants of the solutes in pure water (Kfw) were determined by extrapolation. The thermodynamic parameters (AH ~ and AS ~ and dissociation constants Kam for the solutes in this chromatographic system were obtained by means of capacity factor (k) values using a corresponding model formulation.