title: Covalent immobilization of DNA onto functionalized mica for atomic force microscopy.
abstract: The immobilization of DNA on the self-assembled monolayer of 3-aminopropyltrimethoxysilane (APTES) on mica wafer functionalized with glutaraldehyde (GA) by chemical bonding was studied by atomic force microscopy (AFM). The DNA used for our investigation was amplified by polymerase chain reaction, and primers were labeled with a -NH2 group at their 5' terminus. The surfaces were analyzed by X-ray photoelectron spectroscopy (XPS) and AFM. Results from XPS and AFM showed that the mica with the APTES and activated with GA can be formed, and the flatness of the mica can be adapted for AFM images. We found that the modified surface was capable of binding DNA molecules so that it withstood a thorough rinsing with a solution of sodium dodecylsulfate. Covalent binding between the aldehyde-terminated membrane and -NH2 groups at both ends of double-stranded DNA resulted in immobilization and straightening of the DNA.
authors.affiliation: Key Laboratory for Molecular and Bio-molecular Electronics of Ministry of Education, Nanjing, 210096, China.
authors.forename: Meiju
authors.initials: M
authors.lastname: Ji
authors.forename: Peng
authors.initials: P
authors.lastname: Hou
authors.forename: Zuhong
authors.initials: Z
authors.lastname: Lu
authors.forename: Nongyue
authors.initials: N
authors.lastname: He
mesh_terms: D000538:Aluminum Silicates / Q000737:chemistry*; D004247:DNA / Q000737:chemistry*; D012321:DNA-Directed RNA Polymerases / Q000737:chemistry; D003902:Detergents / Q000494:pharmacology; D004577:Electron Probe Microanalysis; D005976:Glutaral / Q000737:chemistry; D006801:Humans; D018625:Microscopy, Atomic Force / Q000295:instrumentation* / Q000379:methods*; D009690:Nucleic Acid Conformation; D016133:Polymerase Chain Reaction; D011437:Propylamines; D012821:Silanes / Q000737:chemistry; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry; D013270:Stomach / Q000166:cytology
chemical_list: D000538:Aluminum Silicates; D003902:Detergents; D011437:Propylamines; D012821:Silanes; D012967:Sodium Dodecyl Sulfate; D004247:DNA; D012321:DNA-Directed RNA Polymerases; C477625:amino-propyl-triethoxysilane; D005976:Glutaral; C011934:mica