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以琼脂糖凝胶电泳研究了波长为４２７～４５７ｎｍ可见光照射下核黄素（ＶＢ２）光敏诱导的质粒ＤＮＡ损伤，结果发现ＤＮＡ光敏损伤主要与照光量、核黄素和ＤＮＡ浓度比。溶液中的氧气等有关．在无氧条件下光敏损伤更为显著，证明ＶＢ２光敏损伤ＤＮＡ主要是通过ＶＢ２激发三重态与ＤＮＡ碱基组分间发生电荷转移导致其产生氧化性损伤实现的．表明核黄素光敏损伤ＤＮＡ时最佳浓度比为ｂｐ：ＶＢ２＝３．５：１．对照结果表明，单链ＤＮＡ（ｓｓＤＮＡ）比双链ＤＮＡ（ｄｓＤＮＡ）的碱基更易被核黄素敏化发生损伤，这可能是由于ｓｓＤＮＡ中碱基暴露的原因．
The plasmid DNA damage induced by riboflavin (VB2) under visible light irradiation at a wavelength of 427-457 nm was studied by agarose gel electrophoresis. The results showed that the photosynthetic DNA damage was mainly related to the amount of light, riboflavin and DNA concentration. Oxygen in the solution and so on. Under anaerobic conditions, the photodamage was even more pronounced. It was proved that the photodamaged DNA of VB2 is mainly caused by the charge transfer between VB2 excited triplet state and the base component of DNA, resulting in oxidative damage. Show that the optimal concentration ratio of riboflavin photodamaging DNA is bp:VB2=3.5:1. The control results showed that single-stranded DNA (ssDNA) is more susceptible to riboflavin sensitization than bases of double-stranded DNA (dsDNA), which may be due to the exposure of bases in ssDNA.