title: Adhesion-induced DNA naturation.
abstract: DNA adsorption and naturation is modeled via two interacting flexible homopolymers coupled to a solid surface. DNA denatures if the entropy gain for unbinding the two strands overcomes the loss of binding energy. When adsorbed to a surface, the entropy gain is smaller than in the bulk, leading to a stronger binding and, upon neglecting self-avoidance, absence of a denatured phase. Now consider conditions where the binding potentials are too weak for naturation, and the surface potential too weak to adsorb single strands. In a variational approach it is shown that their combined action may lead to a naturated adsorbed phase. Conditions for the absence of naturation and adsorption are derived too. The phase diagram is constructed qualitatively.
authors.affiliation: Yerevan Physics Institute, Alikhanian Brothers Street 2, Yerevan 375036, Armenia.
authors.forename: A E
authors.initials: AE
authors.lastname: Allahverdyan
authors.forename: Zh S
authors.initials: ZhS
authors.lastname: Gevorkian
authors.forename: Chin-Kun
authors.initials: CK
authors.lastname: Hu
authors.forename: Th M
authors.initials: TM
authors.lastname: Nieuwenhuizen
mesh_terms: D004247:DNA / Q000737:chemistry*; D008956:Models, Chemical; D009691:Nucleic Acid Denaturation; D000267:Tissue Adhesions
chemical_list: D004247:DNA