电化学石英晶体微天平研究界面电场对DNA杂交的影响

采用电化学石英晶体微天平, 现场监测不同界面电场下完全匹配的靶标DNA和不完全匹配的靶标DNA分别与寡聚核苷酸探针分子杂交的过程. 结果表明, 电极表面荷正电时DNA表观杂交效率比电极表面荷负电时高, 但假阳性比较显著; 而电极表面荷负电时能有效地抑制错配杂交. 探讨了引入界面电场后探针分子取向和微观作用力对DNA杂交的影响.

Effect of Interface Electric Field on DNA Hybridization Studied by Electrochemical Quartz Crystal Microbalance

The hybridization of oligonucleotide probe with matched or mismatched DNA target was monitored by a combination of electrochemical control and in situ quartz crystal microbalance technique.The results indicated that the apparent efficiency of hybridization for matched DNA target at a positive potential was higher than that at a negative potential.But an obvious response of"false positives"may be obtained at the positive potential.Application of negative potential can availably halt hybridization for mismatched target DNA.The effect of the orientation of oligonucleotide probe and micro forces on DNA hybridization under interface electric field was discussed.