Effect of salt concentration on the strength and specificity of PNA–DNA duplexes and the corresponding DNA–DNA duplexes

<p><b>Copyright information:</b></p><p>Taken from "Diagnosis of HNF-1α mutations on a PNA zip-code microarray by single base extension"</p><p>Nucleic Acids Research 2005;33(2):e19-e19.</p><p>Published online 01 Feb 2005</p><p>PMCID:PMC548378.</p><p>© The Author 2005. Published by Oxford University Press. All rights reserved</p> Three different PNA or DNA zip sequences (Zip3, 7, and 9 in ) were used to prepare the respective zip-code microarrays. This was followed by hybridization for 3 h with a 10 nM solution of 25mer 3′-Cy3-labeled DNA (5′-AAGAAGAAAAAGGA-Cy3-3′, the sequence complementary to the Zip7 sequence is bolded and underlined.) at various ionic strengths. () Fluorescence intensities of perfectly matched PNA–DNA and DNA–DNA duplexes. () The discrimination ratio for PNA–DNA and DNA–DNA complexes, which was defined as the ratio of the signal intensity for a perfectly matched duplex (PM) to the average of the respective intensities obtained with the other two mismatched duplexes (MM)