作　　者： ; ; ; ; ;

机构地区： 广东技术师范学院电子与信息学院

出　　处： 《华南师范大学学报（自然科学版）》 2010年第1期52-57,共6页

摘　　要： 使用2种不同质量分数(4%和6%)的线性聚丙烯酰胺(Linear Polyacrylamide,LPA)作为筛分介质,对片段长度为80～584bp的标准DNA样品进行毛细管电泳.利用激光诱导荧光方法检测信号,荧光染料为溴化乙啶.改变电场强度从100～375V/cm,得到电泳电流、迁移率、信号强度、半峰宽以及分辨率的变化曲线.实验测得电场强度与电流有很好的线性关系,非线性度参数γ分别为0.99944和0.99876.迁移率曲线与电场强度、DNA片段长度成复杂的函数关系,DNA的迁移率依赖于电场强度、筛分介质质量分数和片段长度;电场强度对信号强度的影响较小,筛分介质的质量分数对区带展宽有影响,因此也影响了信号强度,使用4%LPA比6%LPA区带展宽小,信号强度高,更适合分离片段长度≤600bp的DNA样品.电场强度对分辨率的影响十分复杂,增大电场强度并不能提高分辨率,为了提高分辨率,优化分离电场强度为125V/cm,理论分析对实验起到了很好的指导作用. Capillary electrophoresis of DNA fragments（from 80 bp to 584 bp） in replaceable linear polyacrylamide（LPA） solution was investigated using laser induced fluorescence detection.The fluorescence dye was Ethidium Bromide（EB）.When the electric field strength was changed from 100 V/cm to 375 V/cm,the variation curves about current,mobility,signal intensity,width at half-height and the resolution were obtained.The nonlinearity parameter of experimental current and electric field strength are 0.999 44 and 0.998 76 with 4%LPA and 6%LPA respectively,which shows good linear relationships.The mobility is varied as a complex function of fragment size and electric field; the electrophoresis mobility depends on the applied electric field strength,the concentration of gel matrix and the size of the fragment.The electric field strength has effect on the signal intensity little,but the gel matrix concentration affects the peak width so it affects the signal intensity.The broadening is less and signal intensity is higher with 4% LPA than that with 6% LPA.It shows 4% LPA is more suitable for separating DNA samples which the fragment size ≤600 bp.The electric field strength affects resolution complicatedly; the resolution cannot be increased if only increasing the electric field strength.In order to increase the resolution,the optimum electric field strengths are 125 V/cm.The analysis above is very useful for experiment.

关 键 词： 毛细管电泳 电场强度 迁移率 分辨率

领　　域： [理学] [理学]