Denaturation of dsDNA immobilised at a negatively charged gold electrode is not caused by electrostatic repulsion
Double-stranded DNA immobilised through a thiol anchor at a gold electrode surface can be unwound and denatured by applying a negative potential. One proposed mechanism for this electrochemical denaturation is that electrostatic field effects are responsible for the destabilisation of the dsDNA thro...
| Main Authors: | , , , , |
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| Format: | Journal article |
| Language: | English |
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2013
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| _version_ | 1797092248417992704 |
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| author | Johnson, R Gale, N Richardson, J Brown, T Bartlett, P |
| author_facet | Johnson, R Gale, N Richardson, J Brown, T Bartlett, P |
| author_sort | Johnson, R |
| collection | OXFORD |
| description | Double-stranded DNA immobilised through a thiol anchor at a gold electrode surface can be unwound and denatured by applying a negative potential. One proposed mechanism for this electrochemical denaturation is that electrostatic field effects are responsible for the destabilisation of the dsDNA through repulsion of the DNA sugar-phosphate backbone away from the electrode surface. Herein, we demonstrate conclusively that electrochemical melting at gold electrodes cannot be explained solely as a simple repulsion mechanism by showing that immobilised DNA denatures at high ionic strengths, where the DNA base-pairs are situated outside of the electrochemical double-layer (and outside the influence of the electric field), and further, that oligomers comprised of the mimic peptide nucleic acid (PNA) can also be denatured at negative potentials, despite the absence of a negatively charged backbone. This journal is © The Royal Society of Chemistry 2013. |
| first_indexed | 2024-03-07T03:43:25Z |
| format | Journal article |
| id | oxford-uuid:bea65291-0f2b-48c9-8b51-0726ed0c4a8c |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-07T03:43:25Z |
| publishDate | 2013 |
| record_format | dspace |
| spelling | oxford-uuid:bea65291-0f2b-48c9-8b51-0726ed0c4a8c2022-03-27T05:41:18ZDenaturation of dsDNA immobilised at a negatively charged gold electrode is not caused by electrostatic repulsionJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:bea65291-0f2b-48c9-8b51-0726ed0c4a8cEnglishSymplectic Elements at Oxford2013Johnson, RGale, NRichardson, JBrown, TBartlett, PDouble-stranded DNA immobilised through a thiol anchor at a gold electrode surface can be unwound and denatured by applying a negative potential. One proposed mechanism for this electrochemical denaturation is that electrostatic field effects are responsible for the destabilisation of the dsDNA through repulsion of the DNA sugar-phosphate backbone away from the electrode surface. Herein, we demonstrate conclusively that electrochemical melting at gold electrodes cannot be explained solely as a simple repulsion mechanism by showing that immobilised DNA denatures at high ionic strengths, where the DNA base-pairs are situated outside of the electrochemical double-layer (and outside the influence of the electric field), and further, that oligomers comprised of the mimic peptide nucleic acid (PNA) can also be denatured at negative potentials, despite the absence of a negatively charged backbone. This journal is © The Royal Society of Chemistry 2013. |
| spellingShingle | Johnson, R Gale, N Richardson, J Brown, T Bartlett, P Denaturation of dsDNA immobilised at a negatively charged gold electrode is not caused by electrostatic repulsion |
| title | Denaturation of dsDNA immobilised at a negatively charged gold electrode is not caused by electrostatic repulsion |
| title_full | Denaturation of dsDNA immobilised at a negatively charged gold electrode is not caused by electrostatic repulsion |
| title_fullStr | Denaturation of dsDNA immobilised at a negatively charged gold electrode is not caused by electrostatic repulsion |
| title_full_unstemmed | Denaturation of dsDNA immobilised at a negatively charged gold electrode is not caused by electrostatic repulsion |
| title_short | Denaturation of dsDNA immobilised at a negatively charged gold electrode is not caused by electrostatic repulsion |
| title_sort | denaturation of dsdna immobilised at a negatively charged gold electrode is not caused by electrostatic repulsion |
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