𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Assay and Analysis for Anti- and Pro-Oxidative Effects of Ascorbic Acid on DNA with the Bulk Acoustic Wave Impedance Technique

✍ Scribed by Bin Guo; Yu Yuan; Yaohui Wu; Qingji Xie; Shouzhuo Yao


Publisher
Elsevier Science
Year
2002
Tongue
English
Weight
160 KB
Volume
305
Category
Article
ISSN
0003-2697

No coin nor oath required. For personal study only.

✦ Synopsis


A bulk acoustic wave (BAW) impedance sensor has been applied for in situ monitoring of the whole process of DNA oxidative damage induced by the vitamin C (Vc)-Fe (III) system, based on its real-time responses to the density-viscosity change of the tested solution due to the damages occurring on the DNA molecules. The results showed that Vc exhibited two conflicting effects, i.e., pro-oxidation and anti-oxidation on the DNA at different Vc concentrations in the damage system, and the "threshold" concentration of Vc for these two effects was estimated to be about 100 mol/L. The end-point frequency change of the sensor (⌬f m ) was found to be linearly related to the initial concentration of the soybean DNA (C DNA ) in the range of 40 -1000 g/mL, and the exponential relationship between the frequency change (⌬f 0 ) vs damaging time suggested that the Fe (III)-mediated DNA damage by Vc could be described as a first-order kinetics reaction. The effects of variations in concentrations of Vc and Fe 3؉ on the DNA oxidative damage were discussed, and based on investigations for the enhancing influence of H 2 O 2 and inhibiting influence of HO • scavengers on the DNA damage, the nature and physiological toxicity of the damage in biological system were also examined. In addition, UV-vis spectra and electrophoresis analysis were also used, and the experimental observations were in good agreement with the above results.