TY - JOUR
T1 - Photoinduced Reaction of Excited Triplet 9,10-Anthraquinone Quenched by Antioxidant Vitamin C
AU - Chen , Sha
AU - Cao , Xian-Jun
AU - Luo , Yi
AU - Zhu , Guang-Lai
AU - Xu , Xin-Sheng
JO - Journal of Atomic and Molecular Sciences
VL - 3
SP - 238
EP - 246
PY - 2014
DA - 2014/05
SN - 5
DO - http://doi.org/10.4208/jams.031814.061714a
UR - https://global-sci.org/intro/article_detail/jams/8309.html
KW - 9,10-anthraquinone, Vitamin C, time-resolved electron paramagnetic resonance (TREPR)
KW - transient absorptive spectrum, chemically induced dynamic electron polarization (CIDEP).
AB - <p style="text-align: justify;">The quenching of the photoinduced excited triplet of 9,10-anthraquinone $(^3AQ^*)$ by Vitamin C (VC) has been studied in ethylene glycol-water $(EG-H_2O, EG/H_2O=9/1, v/v)$ homogeneous by using time-resolved electronic paramagnetic resonance
(TR-EPR) and laser flash photolysis techniques. According to the chemically
induced dynamic electron polarization (CIDEP) and transient absorptive spectra, the
reaction intermediates and the reaction mechanism have been analyzed. The rate constant
for the quenching of excited triplet $^3AQ^*$ by VC has been measured. The results
indicate that $^3AQ^*$ can capture hydrogen atom not only from ethylene glycol molecule
but also from VC. The strong CIDEP signal of VC monoanion radical indicates that the
quenching of VC to $^3AQ^*$ is obvious. The rate for the quenching of $^3AQ^*$ by VC is
nearly diffusion-controlled.</p>