The development of an Electrochemical Sensor for measuring and detecting circulating tumour DNA in human fluidsB. A O Attoye1, D. Corrigan 2, Centre for Doctoral Training Medical Devices 3 1 LT730 Livingstone Tower Building, University of Strathclyde, Glasgow, G1 1XQ. 2 Biomedical Engineering Department, Level 8. Graham Hills Building, 16 Scotland Rd Richmond Street G11XQ 3 Technology & Innovation Centre, University of Strathclyde, 99 George Street Glasgow G1 1RD.IntroductionCancer arises from small insertions or deletions of nucleotides, polymorphic alterations in the human genome and mutation-originated sequence variations which all play important precursor roles in the development of cancer. Activated KRAS mutations are very common and take place in approximately 90% of pancreatic cancers, 30% of lungs, 60% of thyroid and 43% of colorectal carcinomas. This project aims to develop a nano-sensor that can accurately detect circulating tumour DNA using electrochemical methods.MethodsThe simplicity and affordability of carbon electrodes has made them suitable for characterizing the process in electrochemistry. Carbon electrodes are chemically inert at negative potential ranges in all media giving them an advantage over metal electrodes. Voltammetry and electrochemical impedance spectroscopy were used to analyse the electrochemical activity of unmodified and DNA modified electrodes. Redox agents’ were compared to decide on what was most suitable for measuring DNA hybridization. An isothermal PCR reaction for ctDNA was developed to amplify DNA from patients negative and positive for the KRAS G12D mutation. DNA hybridization measurements were carried out to determine whether differential binding could be determined from such samples.Results & ConclusionAn electrochemical measurement protocol and a suitable redox media was established for measuring electron transfer using screen printed carbon electrodes. The desired number of expected amplicons were obtained after amplification of clinical samples and an increase in charge transfer resistance was observed between the matched analytes and targets. Simultaneous detection of the common KRAS mutations in synthetic oligonucleotides reflected a similar detection in clinical samples.AcknowledgmentsI acknowledge the CDT Medical Devices and EPSRC with grant reference number EP/L015595/1 for the support and sponsorship. I am grateful to the EPSRC Medical Engineering Initiative and the Bioengineering Society for supporting this conference.
|Number of pages||1|
|Publication status||Published - 5 Sep 2018|
|Event||BioMedEng18 - Imperial College, London, United Kingdom|
Duration: 6 Sep 2018 → 7 Sep 2018
|Period||6/09/18 → 7/09/18|
- human fluids
- electrochemical sensor