al-Kazwini A T, O'Neill P, Adams G E, Fielden E M
MRC Radiobiology Unit, Chilton, Didcot, Oxon, United Kingdom.
Radiat Res. 1990 Feb;121(2):149-53.
The "in-pulse" luminescence emission from solid DNA produced upon irradiation with electron pulses of energy below 260 keV has been investigated in vacuo at 293 K to gain an insight into the existence of radiation-induced charge/energy migration within DNA. The DNA samples contained misonidazole in the range 3 to 330 base pairs per misonidazole molecule. Under these conditions greater than 90% of the total energy is deposited in the DNA. The in-pulse radiation-induced luminescence spectrum of DNA was found to be critically dependent upon the misonidazole content of DNA. The luminescence intensity from the mixtures decreases with increasing content of misonidazole, and at the highest concentration, the intensity at 550 nm is reduced to 50% of that from DNA only. In the presence of 1 atm of oxygen, the observed emission intensity from DNA in the wavelength region 350-575 was reduced by 35-40% compared to that from DNA in vacuo. It is concluded that electron migration can occur in solid mixtures of DNA over a distance of up to about 100 base pairs.
为深入了解DNA内辐射诱导的电荷/能量迁移情况，在293K真空条件下，研究了能量低于260keV的电子脉冲辐照固态DNA产生的“脉冲内”发光发射。DNA样品中每分子米索硝唑含3至330个碱基对。在这些条件下，超过90%的总能量沉积在DNA中。发现DNA的脉冲内辐射诱导发光光谱严重依赖于DNA的米索硝唑含量。混合物的发光强度随米索硝唑含量增加而降低，在最高浓度时，550nm处的强度降至仅DNA的50%。在1个大气压氧气存在下，与真空条件下DNA的发射强度相比，在350 - 575nm波长区域观察到的DNA发射强度降低了35 - 40%。得出结论，电子迁移可在DNA的固态混合物中发生，距离可达约100个碱基对。
