杂交及切断过程的QCM实时检测研究(英文)

采用自组装技术,将 5′端标记有巯基的 20-merODN(oligo 1)以金 硫键形式牢固结合在 7. 995MHz的AT-切石英晶体的镀金表面,然后由石英晶体微天平实时检测了与碱基序列互补的 10 merODN (oligo 2)和 8 merODN(oligo 3)的杂交,同时还研究了稀土金属铈离子在温和条件下对DNA的水解切断作用.结果表明:应用QCM方法可能实时检测DNA的固定和杂交,Ce(IV)能随机切断单链DNA;但不能切断杂交形成的双链DNA,因此可利用杂交保护的方法对单链DNA实行定位切断.

In-situ Measurements of Single-stranded DNA Hybridization and Cleavage by Quartz Crystal Microbalance

The use of quartz crystal microbalance (QCM) for in-situ monitoring the immobilization of single-stranded DNA(oligo-1), marked with mercaptol group at 5' end, on the surface of gold-filled 7.995 MHz AT-cut quartz crystal by Au-S bond with self-assemble technique is reported. And then the hybridization of ssDNA with the complementary 10-mer ODN(oligo-2) and 8-mer ODN(oligo-3) is described. Moreover, the QCM has been employed to analyze the DNA cleavage by cerium(IV) ions under moderate conditions. The results showed that the QCM, which is capable of sensitive measurement, was able to in-situ investigate immobilization, hybridization and cleavage of ssDNA. And the cerium(IV) ions had no cleavage for the double-stranded DNA, but it could hydrolyze single-stranded DNA. So the hydrolytic cleavage of ssDNA at the specific site could be realized by the protection of the hybridization.