
Detection of thymine stretches in DNA oligonucleotides at the surface of hanging mercury drop electrode using thymine-mercury base pair formation
Autoři | |
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Rok publikování | 2025 |
Druh | Článek v odborném periodiku |
Časopis / Zdroj | Electrochimica Acta |
Fakulta / Pracoviště MU | |
Citace | |
www | https://www.sciencedirect.com/science/article/pii/S0013468624017341?via%3Dihub |
Doi | http://dx.doi.org/10.1016/j.electacta.2024.145498 |
Klíčová slova | Thymine; Mercury ions; Base pair; Cyclic voltammetry; Hanging mercury drop electrode |
Popis | Thymine-mercury-thymine base pair is a well described type of metal ion-mediated interaction in DNA, with a frequent use in construction of biosensors for mercury detection. In this work we took advantage of this interaction to study behavior of thymine-containing oligodeoxynucleotide (ODN) layers adsorbed on the surface of hanging mercury drop electrode (HMDE), which served as a source of mercury cations upon applying a mildly positive potential (+0.15 V). We confirmed formation of the thymine-mercury complex at the surface of HMDE by observing a pair of redox peaks specific for mercury in dependence on presence of the thymine stretches in ODNs. Deoxythymidine mono- or triphosphate gave much weaker signals due to the mercury-thymine complexes. We confirmed that the complex formation can cause unwinding of the AT duplex and concluded that this approach can be used to observe desorption of the homothymine ODN from the HMDE surface. Moreover, we were able to detect stretches of as little as three thymines in ODNs derived from different telomeric repeat sequences. |