【摘要】 本文以λDN/HinaⅢ片段(2.0kbp至23.1kbp)为材料,研究在各价态金属离子作用下DNA片段在凝胶中电泳迁移率的变化规律.离子效应使DNA聚合链的挠性增大,末端距与持久长度减小,从而使电泳迁移率随离子强度的增加而减小;同时这种离子效应又是价态依赖的.DNA电泳行为的离子效应与Hervet关于DNA聚合键在凝胶中的电泳理论模型分析一致.同时尝试应用现代多聚电解质理论对电泳离子效应的半定量分析也得到了满意的结果.本文还对凝胶浓度、电场强度、以及分子量诸因素对DNA电泳性质的影响进行了实验研究与讨论.更多还原

【Abstract】 λ DNA/Hind Ⅲ fragments (from 2.0×103 to 23.1×103 base pairs) were used to investigate electrophoretic mobility of DNA in agarose gels when interacting with metal ions of different valence. The flexibility and persistence length of DNA chains have been changed after adding ions in solution, therefore, the electrophoretic mobility decreased with increasing of ionic strength; furthermore, the effect of ions is valencn dependent. The behavior of DNA in agarose gel under the effect of ions is consistent with the theoretical model of DNA chains in agarose gel. It is also satisfactory to analyse the above phenomena semiquanti-tatively by modern poly-electrolyte theory. Experimental studies of the various parameters: gel concentration, electric field, and molecular weight, have also been performed.更多还原