[Determination of ascorbic acid by suppressed chemiluminescence].
This paper describes a method for determining ascorbic acid by the suppression of DTMC-H2O2 chemiluminescence. Various factors affecting the chemiluminescence determination of ascorbic acid were examined. Under the optimal conditions (1.2 x 10(-4) mol.L-1 of DTMC, 5.0 x 10(-5) mol.L-1 of H2O2, and pH 11.4 Na2HPO4-NaOH), the quenching of the chemiluminescent intensity was proportional to the concentration of ascorbic acid in the range of 1.0 x 10(-7)-8.0 x 10(-6) mol.L-1, and the detection limit was 8.0 x 10(-8) mol.L-1 (S/N = 3). The RSD was 4.6% for 1.0 x 10(-6) mol.L-1 of ascorbic acid (n = 10). The selectivity of this method was high and no making agent required. The proposed method has been applied to the determination of ascorbic acid in real samples. The obtained results were in agreement with those by CuSO4-KI titration.
Ma
Quan-li
QL
Center for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China.
Jin
Yong-ping
YP
You
Hong-tao
HT
Ma
Hui-min
HM
D001205:Ascorbic Acid / Q000032:analysis*; D007202:Indicators and Reagents; D008163:Luminescent Measurements; D013050:Spectrometry, Fluorescence
D007202:Indicators and Reagents; D001205:Ascorbic Acid