Determination of hydroxyl radical by capillary zone electrophoresis with amperometric detection.
Hydroxyl radical (OH*) can cause severe damage to cells and tissues. However, its analysis is very difficult for its high reactivity and very short half-life. In this paper, a simple and highly sensitive method, capillary zone electrophoresis with amperometric detection (CZE-AD) was introduced indirectly to determine OH* by determining its reaction products with salicylic acid (SAL), 2,3-dihydroxybenzoic acid (2,3-DHBA) and 2,5-dihydroxybenzoic acid (2,5-DHBA). The optimum conditions of CZE-AD for the determination of 2,3-DHBA and 2,5-DHBA were explored. Under the optimum conditions, SAL, 2,3-DHBA and 2,5-DHBA could be perfectly separated within 15 min, and the linearity ranges of 2,3-DHBA and 2,5-DHBA were between 1.0 x 10(-7) and 1.0 x 10(-4) mol l(-1). Their detection limits were as low as 2 x 10(-8) mol l(-1), which were much lower than that in CE-UV method. The method was also applied to study the free OH* scavenging activity of angelica polysaccharide. The experimental results showed that this CZE-AD method was very sensitive and practical in both the determination of free OH* and the evaluation of free OH* scavenging activities of antioxidants.
Wang
Qingjiang
Q
Department of Chemistry, East China Normal University, Shanghai 200062, China.
Ding
Fei
F
Zhu
Ningning
N
Li
Hui
H
He
Pingang
P
Fang
Yuzhi
Y
D004563:Electrochemistry / Q000379:methods*; D019075:Electrophoresis, Capillary / Q000379:methods*; D016166:Free Radical Scavengers / Q000737:chemistry; D017665:Hydroxyl Radical / Q000737:chemistry*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D016166:Free Radical Scavengers; D017665:Hydroxyl Radical