A universal peroxyoxalate-chemiluminescence detection system for mobile phases of differing pH.
A universal peroxyoxalate-chemiluminescence detection system for high performance liquid chromatography, available for a variety of mobile phases, has been developed. The system consisted of a dual-head short-stroke pump and a chemiluminescence detector. The standard conditions using bis(2,4,6-trichlorophenyl) oxalate (TCPO) as aryl oxalate were as follows. The first postcolumn solution was the mixture of 0.5 M imidazole-nitric acid (pH 7.5) and acetonitrile (1:4, v/v). The second was acetonitrile containing TCPO-hydrogen peroxide. These two solutions were delivered by the two pump-heads. After the pH of the column eluate was adjusted to the optimum range (6.5-7.5) by the first postcolumn solution, the solution was mixed with the second postcolumn solution. After flowing through a reaction coil, the chemiluminescence of the mixture was monitored. Using this system, a high sensitivity (fmol level) was obtained for perylene as an analyte with mobile phases having different pH values (2.0-8.0). Polycyclic aromatic hydrocarbons became detectable to a high sensitivity even after the column separation using an acidic mobile phase. The detection sensitivity of nitrated pyrenes after on-line electrochemical reduction using an acidic mobile phase was also increased. This system might be available for other aryl oxalates by some modifications of the postcolumn solutions.
Hayakawa
K
K
Faculty of Pharmaceutical Sciences, Kanazawa University, Japan.
Minogawa
E
E
Yokoyama
T
T
Miyazaki
M
M
Imai
K
K
D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D017022:Flow Injection Analysis; D006863:Hydrogen-Ion Concentration; D008163:Luminescent Measurements; D010070:Oxalates / Q000737:chemistry*
D010070:Oxalates; C044622:peroxyoxalate