Electrophoresis, Vol.30, No.13, 2258-2265, 2009
Separation of free amino acids and catecholamines in human plasma and rabbit vitreous samples using a new fluorogenic reagent 3-(4-bromobenzoyl)-2-quinolinecarboxaldehyde with CE-LIF detection
A sensitive and efficient analysis of amino acids and catecholamines is currently presented with 3-(4-bromobenzoyl)-2-quinolinecarboxaldehyde as a fluorogenic derivatization reagent using CE separation with LIF detection. For good derivatization conditions, the reagent concentrations, pH value, temperature, and reaction time were explored, which were followed by the derivatization reaction in stable yield. The optimal running buffer was composed of mixtures involving 120 mM, pH 9.1 boric acid, 38.5 mM SDS, and 19% ACN v/v. The LOD (S/N = 3) was found as low as 0.65 nM. The proposed method was validated by the two-order-magnitude linearity and correlation coefficient ranging from 0.9957 to 0.9998. The accuracy and specificity of this assay were also assured from the spiking of real samples with a standard known concentration. In order to demonstrate its wide range of applications, the method has been applied to the analysis of both human plasma and rabbit vitreous samples.