Precolumn derivatization for improved detection in liquid chromatography-photolysis-electrochemistry.
Precolumn, homogeneous chemical derivatization with Sanger's reagent (2,4-dinitrofluorobenzene) is utilized to improve the chromatographic and detection properties of amino alcohols and amino acids. The 2,4-dinitrophenyl derivatives are separated using reversed-phase liquid chromatography and are detected using the hybrid photolysis-electrochemical (hv-EC) detector in tandem with UV absorbance detection. Following optimization of reaction, chromatographic, and detection variables, the derivatization-detection approach provides limits of detection in the low parts-per-billion range, with a linearity of roughly three orders of magnitude. Selectivity is based on retention times as well as dual electrode response ratios and a "lamp on/off" responsiveness criterion unique to the hv-EC detector. The method is applied to the determination of serine in beer.
Chang
M Y
MY
Barnett Institute of Chemical Analysis, Northeastern University, Boston, Massachusetts 02115.
Chen
L R
LR
Ding
X D
XD
Selavka
C M
CM
Krull
I S
IS
Bratin
K
K
D000596:Amino Acids / Q000032:analysis*; D000605:Amino Alcohols / Q000032:analysis*; D002853:Chromatography, Liquid / Q000379:methods*; D004139:Dinitrofluorobenzene; D004563:Electrochemistry
D000596:Amino Acids; D000605:Amino Alcohols; D004139:Dinitrofluorobenzene