Umemura K, Ishikawa M, Kuroda R
Joint Research Center for Atom Technology--Angstrom Technology Partnership, 1-1-4, Higashi, Tsukuba, Ibaraki 305-0046, Japan.
Anal Biochem. 2001 Mar;290(2):232-7. doi: 10.1006/abio.2001.4996.
Immobilization of biomolecules on surfaces while keeping the maximum conformational flexibility of the molecules is one of the most important techniques for atomic force microscopy imaging. We have developed two methods of controlling adsorption of DNA molecules on mica surfaces. The first method is the use of a mica surface modified with diluted 3-aminopropyltriethoxysilane (APS). Here we named this a "diluted APS-treated mica (AP-mica)" technique. The second method is the use of a mica surface modified with mixed self-assembled monolayers of organosilanes. In both of the techniques, the number of DNA molecules immobilized on a mica surface was controlled. Further, a conformational change of circular DNA, from a supercoiled to a relaxed form was observed for the molecules immobilized on a diluted AP-mica surface, when 254-nm UV light was irradiated. This observation demonstrated that flexibility of circular DNA molecules was kept on a diluted AP-mica surface.
在保持生物分子最大构象灵活性的同时将其固定在表面上，是原子力显微镜成像最重要的技术之一。我们开发了两种控制DNA分子在云母表面吸附的方法。第一种方法是使用用稀释的3-氨丙基三乙氧基硅烷（APS）修饰的云母表面。在此我们将此命名为“稀释APS处理的云母（AP-云母）”技术。第二种方法是使用用有机硅烷的混合自组装单分子层修饰的云母表面。在这两种技术中，固定在云母表面的DNA分子数量都得到了控制。此外，当用254纳米紫外光照射时，观察到固定在稀释的AP-云母表面的环状DNA分子从超螺旋形式转变为松弛形式。这一观察结果表明环状DNA分子在稀释的AP-云母表面上保持了灵活性。
