Dual-cloud point extraction and tertiary amine labeling for selective and sensitive capillary electrophoresis-electrochemiluminescent detection of auxins

作者：Yin Xue Bo^*; Guo Jun Min; Wei Wei

来源：Journal of Chromatography A, 2010, 1217(8): 1399-1406.

DOI：10.1016/j.chroma.2009.12.029

• Auxin
• Capillary electrophoresis
• Electrochemiluminescence
• Dual-cloud point extraction
• Tertiary amine labeling

The low concentrations of the auxins in samples of plant tissue necessitate the use of selective and sensitive techniques for their quantification Herein a selective and sensitive method based on dual-cloud point extraction (dCPE) and tertiary amine labeling for the quantification of indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA) by capillary electrophoresis-electrochemiluminescence (CE-ECL) is proposed The procedure foe dCPE included two cloud point processes with Triton X-114 as the extractant The two auxins became hydrophobic in an acidic solution and were extracted into surfactant-rich phase after the first cloud point procedure They were then back-extracted into the alkaline aqueous phase during the second cloud point step The extracted auxins were reacted with 2-(2-aminoethyl)-1-methylpytrolidine (AEMP) in acetonitrile that contained N,N';-dicyclohexylcarbodimide and 3,4-dihydro-3-hydroxy-4-oxo-1,2,3-benzotriazine to produce their AEMP-derivatives The two auxin-AEMP-derivatives were subjected into CE and detected by Ru(bpy)(3)(2+)-based ECL. The preconcentration factors for IAA and IBA with dCPE were 40.5 and 43.4, respectively The on-capillary detection limits (S/N=3) were 2.5 and 2.8 nM for IAA and IBA This protocol presents a cleat advantage in that it reduces the interference from the matrixes extensively and gives a high sensitivity foe the detection of auxins The proposed method was applied successfully to the detection of the two auxins in acacia tender leaves.

• 出版日期2010-2-19
• 单位南开大学