Optimization of label-free DNA detection with electrochemical impedance spectroscopy using PNA probes

Keighley, Simon D.; Estrela, Pedro; Li, Peng; Migliorato, P.

doi:10.1016/j.bios.2008.07.041

Cited by 91 publications

(60 citation statements)

References 15 publications

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“…These reports attribute the observed change in the impedimetric response to the sensing film structure and the resulting conformational/structural changes which occur on the surfaces of electrodes with different geometries 27 . In this study, the protocol used to prepare the sensor surface resulted in a film conformation which caused an increase in R CT following target binding, which was in keeping with previous macroelectrode studies where increases in R CT were attributed to the target DNA blocking pinholes and increasing electrostatic repulsion at the electrode surface, ultimately causing a decrease in the exchange current density 28 .…”

Section: Page 4 Of 13 Analystsupporting

confidence: 61%

Impedimetric measurement of DNA–DNA hybridisation using microelectrodes with different radii for detection of methicillin resistant Staphylococcus aureus (MRSA)

Piper

Schmueser

et al. 2017

Analyst

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Due to their electroanalytical advantages, microelectrodes are a very attractive technology for sensing and monitoring applications. One highly important application is measurement of DNA hybridisation to detect a wide range of clinically important phenomena, including single nucleotide polymorphisms (SNPs), mutations and drug resistance genes. The use of electrochemical impedance spectroscopy (EIS) for measurement of DNA hybridisation is well established for large electrodes but as yet remains relatively unexplored for microelectrodes due to difficulties associated with electrode functionalisation and impedimetric response interpretation. To shed light on this, microelectrodes were initially fabricated using photolithography and characterised electrochemically to ensure their responses matched established theory. Electrodes with different radii (50, 25, 15 and 5 µm) were then functionalised with a mixed film of 6-mercapto-1-hexanol and a thiolated single stranded ssDNA capture probe for a specific gene from the antibiotic resistant bacterium MRSA. The complementary oligonucleotide target from the mecA MRSA gene was hybridised with the surface tethered ssDNA probe. The EIS response was evaluated as a function of electrode radius and it was found that charge-transfer (R CT ) was more significantly affected by hybridisation of the mecA gene than the non-linear resistance (R NL ) which is associated with the steady state current. The discrimination of mecA hybridisation improved as electrode radius reduced with the R CT component of the response becoming increasingly dominant for smaller radii. It was possible to utilise these findings to produce a real time measurement of oligonucleotide binding where changes in R CT were evident one minute after nanomolar target addition. These data provide a systematic account of the effect of microelectrode radius on the measurement of hybridisation, providing insight into critical aspects of sensor design and implementation for the measurement of clinically important DNA sequences. The findings open up the possibility of developing rapid, sensitive DNA based measurements using microelectrodes.

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Section: Page 4 Of 13 Analystsupporting

confidence: 61%

Impedimetric measurement of DNA–DNA hybridisation using microelectrodes with different radii for detection of methicillin resistant Staphylococcus aureus (MRSA)

Piper

Schmueser

et al. 2017

Analyst

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“…43,44 The covalent insertion of metals into the PNA capture probe seems an interesting alternative to avoid the addition of indicators. The main advantages of such an alternative are the distinct and permanent label-strand bonding and the certainty about the location and the strand bonding of the probe.…”

Section: Pnamentioning

confidence: 99%

Metal-containing peptide nucleic acid conjugates

2011

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Peptide Nucleic Acids (PNAs) are non-natural DNA/RNA analogues with favourable physicochemical properties and promising applications. Discovered nearly 20 years ago, PNAs have recently re-gained quite a lot of attention. In this Perspective article, we discuss the latest advances on the preparation and utilisation of PNA monomers and oligomers containing metal complexes. These metalconjugates have found applications in various research fields such as in the sequence-specific detection of nucleic acids, in the hydrolysis of nucleic acids and peptides, as radioactive probes or as modulators of PNA˙DNA hybrid stability, and last but not least as probes for molecular and cell biology.

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“…Moreover, EIS circumvents the labeling of at least one compound of the assay with, for example, enzymes, fluorophores, or redox reporters and can hence be considered as a label-free approach for detecting complementary recognition events at surfaces. [6][7][8][9] Therefore, EIS has been successfully applied for the detection of DNA conductivity, [10] DNA hybridization, [11][12][13][14][15] single-nucleotide mismatches in double-stranded DNA (dsDNA), [16] in situ hybridization of PNA/DNA, [17] DNA and RNA replication, [18,19] and the interaction of metal ions with DNA. [20,21] DNA detection by means of EIS is based on the repulsion between the DNA-modified electrode and a free-diffusing redox reporter, typically [Fe(CN) 6 ] 3À/4À .…”

Section: Introductionmentioning

confidence: 99%

Controlled Orientation of DNA in a Binary SAM as a Key for the Successful Determination of DNA Hybridization by Means of Electrochemical Impedance Spectroscopy

Gębala

Schuhmann

2010

ChemPhysChem

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Determination of DNA hybridization at electrode surfaces modified with thiol-tethered single-stranded DNA (ssDNA) capture probes and co-assembled with short-chain thiol derivatives using electrochemical impedance spectroscopy requires a careful design of the electrode/electrolyte interface as well as an in-depth understanding of the processes at the interface during DNA hybridization. The influence of the electrode potential, the ssDNA coverage, the ionic strength, the nature of the thiol derivative and especially the Debye length are shown to have a significant impact on the impedance spectra. A mixed monolayer comprising--in addition to the ssDNA capture probe--both mercaptohexanol (MCH) and mercaptopropionic acid (MPA) is suggested as an interface design which allows a high efficiency of the DNA hybridization concomitantly with a reliable modulation of the charge-transfer resistance of the electrode upon hybridization.

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Optimization of label-free DNA detection with electrochemical impedance spectroscopy using PNA probes

Cited by 91 publications

References 15 publications

Impedimetric measurement of DNA–DNA hybridisation using microelectrodes with different radii for detection of methicillin resistant Staphylococcus aureus (MRSA)

Impedimetric measurement of DNA–DNA hybridisation using microelectrodes with different radii for detection of methicillin resistant Staphylococcus aureus (MRSA)

Metal-containing peptide nucleic acid conjugates

Controlled Orientation of DNA in a Binary SAM as a Key for the Successful Determination of DNA Hybridization by Means of Electrochemical Impedance Spectroscopy

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