DNA共价结合在化学修饰云母片上的AFM研究

AFM Studies on DNA Covalently Immobilized on Mica Modified by APTES-GA

原子力显微镜（AFM）自1986年发明以来, 已经成为生物学研究领域中的一个有效工具，尤其在核酸及其它生物大分子结构方面的应用已成为普遍关注的热点.

The immobilization of DNA on self-assembled layers of 3-aminopropyltrimethoxysilane (APTES) and glutaraldehyde(GA) on mica wafers by chemical coupling has been studied by using atomic force microscopy (AFM). The DNA used for our investigation is amplified by PCR and primers were labeled by -NH2 at their 5' terminal. The surfaces were analyzed with X-ray photoelectron spectroscopy (XPS) and AFM. The results from XPS and AFM show that APTES-GA modified mica can be formed and the flatness of mica is adapted to AFM images. We found that DNA can be readily immobilized on mica. The covalent coupling between the aldehyde-terminated membrane and the both H2N-groups in double strands DNA results in the immobilization of the DNA straightly.