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On the binding of cationic, water-soluble conjugated polymers to DNA: electrostatic and hydrophobic interactions.

ABSTRACT: Water-soluble, cationic conjugated polymer binds single-stranded DNA with higher affinity than it binds double-stranded or otherwise "folded" DNA. This stronger binding results from the greater hydrophobicity of single-stranded DNA. Upon reducing the strength of the hydrophobic interactions, the electrostatic attraction becomes the important interaction that regulates the binding between the water-soluble conjugated polymer and DNA. The different affinities between the cationic conjugated polymer and various forms of DNA (molecular beacons and its open state; single-stranded DNA and double-stranded DNA and single-stranded DNA and complex DNA folds) can be used to design a variety of biosensors.

SUBMITTER: Xia F

PROVIDER: S-EPMC2846820 | biostudies-literature | 2010 Feb

REPOSITORIES: biostudies-literature

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On the binding of cationic, water-soluble conjugated polymers to DNA: electrostatic and hydrophobic interactions.

Xia Fan F Zuo Xiaolei X Yang Renqiang R Xiao Yi Y Kang Di D Vallée-Bélisle Alexis A Gong Xiong X Heeger Alan J AJ Plaxco Kevin W KW

Journal of the American Chemical Society 20100201 4

Water-soluble, cationic conjugated polymer binds single-stranded DNA with higher affinity than it binds double-stranded or otherwise "folded" DNA. This stronger binding results from the greater hydrophobicity of single-stranded DNA. Upon reducing the strength of the hydrophobic interactions, the electrostatic attraction becomes the important interaction that regulates the binding between the water-soluble conjugated polymer and DNA. The different affinities between the cationic conjugated polyme ...[more]

PMID: 20058862

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