Electrogenerated Chemiluminescence Detection of Amino Acids Based on Precolumn Derivatization Coupled with Capillary Electrophoresis Separation

Abstract

A novel method for highly sensitive detection of primary and secondary amino acids with selective derivatization using acetaldehyde as a new derivatization reagent was proposed by capillary electrophoresis (CE) coupled with electrogenerated chemiluminescence (ECL) of tris(2,2'-bipyridine)ruthenium(II). The precolumn derivatization of these amino acids with acetaldehyde was performed in aqueous solution at room temperature for 1 h. Upon optimized derivatization, the ECL intensities and detection sensitivities of the amino acids were significantly enhanced by 20-70 times. Using four amino acids, arginine, proline, valine, and leucine, as model compounds, their derivatives could be completely separated by CE and sensitively detected by ECL within 22 min. The linear ranges were 0.5-100 microM for arginine and proline and 5-1000 microM for valine and leucine with the detection limits of 1 x 10(-7) (0.5 fmol, arginine), 8 x 10(-8) (0.4 fmol, proline), 1 x 10(-6) (5 fmol, valine), and 1.6 x 10(-6) M (8 fmol, leucine) at a signal-to-noise ratio of 3. The derivatization reactions and ECL process of amino acids were also proposed based on in situ Fourier transform infrared and ultraviolet spectrometric analyses.

Determination of enoxacin and ofloxacin by capillary electrophoresis with electrochemiluminescence detection in biofluids and drugs and its application to pharmacokinetics

“…Recently, CE-CL has been widely developed and become a useful tool for rapid detection of various analytes such as metal ions (Ren and Huang, 2001), amino acids , proteins (Zhi et al, 2007) and antigen-antibody complexes (Wang and Ren, 2005). The marriage of CE to ECL is a sensitive and effi cient analytical technique and has got excellent performance for the analysis of proteins Guo et al, 2009), amino acids (Li et al, 2006) and drugs (Zhao et al, 2004;Yuan et al, 2009;Liu et al, 2008aLiu et al, , 2009aXu et al, 2006;Deng et al, 2008).…”

Simple Electrochemiluminescence Sensor Based on Nafion-Graphene-Ru(bpy)32+Modified Electrode for the Ultrasensitive Detection of Tetrodotoxin

“…27 The pH of the detection solution mainly affects the efficiency of Ru(bpy) 3 2+ electrooxidation, which was in agreement with the usually optimum pH value of 7.0-8.0. [28][29][30] The ECL response is attributed to protonation of the TPA at low pH, and then depend on formation of excited state Ru(bpy) 3 2+ * . Fig.…”

Chemiluminescence determination of chlorpheniramine using tris(1,10‐phenanthroline)–ruthenium(II) peroxydisulphate system and sequential injection analysis

“…The electrochemiluminescent (ECL) generation of Ru(III) complexes is receiving a lot of interest due to the favourable characteristics of these species, such as excellent chemical stability, high emission quantum yield and long lifetime of the excited state (15,(25)(26)(27)(28)(29)(30)(31)(32). The major limitations of ECL are those associated with electrodes, such as fouling, and the need for reconditioning of the electrode surface to sustain a constant CL signal.…”