【作者】 邵龙义； 李金娟； 赵厚银； 时宗波； 吕森林； Jones T.P.； Richards R.J.；

【Author】 Shao Longyi;Li Jinjuan;Zhao Houyin;Shi Zongbo;Lu Senlin;Jones T.P.;Richards R.J.;Institute of Atmospheric Environment and Pollution Control,China University of Mining and Technology;Department of Resources and Earth Sciences China University of Mining and Technology;School of Biosciences Cardiff University;

【机构】 中国矿业大学(北京校区)大气环境与污染控制研究所； 中国矿业大学(北京校区)资源与地球科学系； School of Biosciences Cardiff University；

【摘要】 质粒DNA评价法是国际上近年来新出现的一种快速、简便地定量评价颗粒物氧化性损伤的方法。其基本原理是根据颗粒物对质粒DNA损伤后会使原始的超螺旋DNA被破坏成松驰状和线化DNA,利用电泳凝胶及紫外凝胶成像系统,以松驰和线化占总质粒的百分比作为颗粒物的生物活性,以此来评价大气颗粒物的毒性。利用这一方法对北京市大气颗粒物对DNA的氧化性损伤能力进行了的初步研究表明,PM_2.5的氧化性损伤能力大于PM₁₀;沙尘暴期间大气颗粒物的氧化性损伤低于非沙尘暴样品;夏季样品低于冬季,市区样品低于郊区。更多还原

【Abstract】 The plasmid assay is a rapid,simple and newly built method for quantifying oxidative stress of airborne particles on plasmid DNA.The basic principle of this method is that any free radicals associated with particle surfaces can damage the super-coiled DNA by "scratching" the strands.This damage initially causes the DNA to unwind from the supercoiled form into a relaxed coil and further damage results in complete linearization followed by fragmentation.This change in quaternary structure alters the electrophoretic mobility of the DNA,thus allowing separation and quantification of different forms of DNA on an agarose gel.Bioreactivity or oxidative capacity of particles can be calculated as the combined amount of DNA in the relaxed and linear（damaged） forms as a proportion of the total amount of DNA.The preliminary application of this method to Beijing PM₁₀s showed that the dust storm particles exerted less oxidative stress on plasmid DNA than non-dust storm particles,and PM_2.5 had much higher oxidative stress than PM₁₀,and the winter PMs had higher oxidative stress than summer PMs,and suburban PMs had higher oxidative stress than urban PMs.更多还原