Vortex-assisted liquid-liquid microextraction coupled with derivatization for the fluorometric determination of aliphatic amines.
A new one-step derivatization and microextraction technique was developed for the fluorometric determination of C(1)-C(8) linear aliphatic primary amines in complex sample solutions containing high levels of amino acids. In this method, amines were derivatized with o-phthalaldehyde (OPA) and 2-mercaptoethanol (2-ME) in aqueous solution and extracted simultaneously by vortex-assisted liquid-liquid microextraction (VALLME). Parameters affecting the extraction efficiency were investigated in detail. The optimum conditions were as follows: 50 μL of isooctane as the extractant phase; 2.0 mL aqueous donor samples with 12 mM OPA, 24 mM 2-ME, and 0.1 M borate buffer at pH 10; 1 min vortex extraction time; centrifugation for 4 min at 6000 rpm. After centrifugation, the enriched analytes in the floated extractant phase were determined by HPLC-FL in less than 14 min. Under the optimum conditions, the limits of detection were of the order of 0.09-0.31 nM. The calibration curves showed good linearity over the investigated concentration range between 0.4 and 40 nM. The proposed method has been applied to the determination of aliphatic amines in acidophilus milk, beer, and Cu(II)/amino acid solution.
Environmental Chemistry Laboratory, Department of Biomedical Engineering and Environmental Sciences, College of Nuclear Science, National Tsing Hua University, Hsinchu 30013, Taiwan.
Wei-Yao
WY
Chang
Chin-Yi
CY
Wang
Jeng-Lyan
JL
Jan
Yu-Shiu
YS
Lo
Chien-Hou
CH
Wu
D000588:Amines / Q000032:analysis / Q000302:isolation & purification*; D000596:Amino Acids / Q000737:chemistry; D000818:Animals; D001515:Beer / Q000032:analysis; D002138:Calibration; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D004785:Environmental Pollutants / Q000032:analysis / Q000302:isolation & purification*; D005470:Fluorometry / Q000379:methods; D006838:Hydrocarbons / Q000032:analysis / Q000302:isolation & purification*; D057230:Limit of Detection; D059627:Liquid Phase Microextraction / Q000379:methods*; D008623:Mercaptoethanol / Q000737:chemistry; D008892:Milk / Q000737:chemistry; D009795:Octanes / Q000737:chemistry; D009764:o-Phthalaldehyde / Q000737:chemistry
D000588:Amines; D000596:Amino Acids; D004785:Environmental Pollutants; D006838:Hydrocarbons; D009795:Octanes; D008623:Mercaptoethanol; D009764:o-Phthalaldehyde; C045798:2,2,4-trimethylpentane