Immobilization of DNA through Intercalation at Self-Assembled Monolayers on Gold

• Published in: Langmuir 1999-01, Vol.15 (1), p.111-115
• Main Authors: Higashi, Nobuyuki, Takahashi, Minoru, Niwa, Masazo
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Biotechnology; Cell immobilization; Chemical bonds; Chemistry; DNA; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; General and physical chemistry; Gold; Molecular structure; Polyesters; Quartz applications; Solid-liquid interface; Substrates; Sulfur compounds; Surface physical chemistry; Synthesis (chemical)
• ISSN: 0743-7463; 1520-5827
• DOI: 10.1021/la9803427

A novel acridine derivative (1) connected with a disulfide bond through a long methylene spacer has been synthesized, and its interactions with DNA in solutions and at a self-assembled monolayer surface on gold have been studied. Spectroscopic and thermal data indicated that 1 intercalated successfully to DNA in buffer solutions. The mixed monolayers of 1 and 2, which has a similar molecular structure to that of 1 except for the lack of the acridine moiety, on gold substrates were then prepared. When DNA binding properties onto these monolayers were examined by means of a quartz crystal microbalance, there was a monolayer composition (mole fraction of 1 in the mixed monolayer, 0.04) at which the most effective binding of DNA took place. The interaction of this DNA-immobilized monolayer with polylysines (d, l) was examined by comparing circular dichroism spectra before and after binding of polylysines, and such a two-dimensionally immobilized DNA was found to have an ability to bind poly-l-lysine predominately.