Novel molecular design and dielectrophoretic manipulation for enhancing biosensors

Condensed Matter lunchtime seminar

Novel molecular design and dielectrophoretic manipulation for enhancing biosensors

  • Event time: 1:00pm
  • Event date: 11th June 2012
  • Speaker: Mira Nishimura (Formerly School of Physics & Astronomy, University of Edinburgh)
  • Location: Room 2511,

Event details

Single nucleotide polymorphisms (SNPs), being the most abundant type of human polymorphisms and relatively well categorised, make good markers to indicate genes that underlie diseases. Therefore there is great interest in the development of biosensors capable of SNP genotyping. A novel biosensor based on the well-studied DNA Holliday junction, designed to detect single base mutations in an unlabelled target sequence through a simple bait-and-switch mechanism has been developed, and applied to both synthetic and clinically-extracted samples. A second mode of enhancing detection sensitivity is through direct manipulation of matter by dielectrophoresis (DEP). DEP arises from the creation of a force acting on an electrically polarized particle when subjected to a non-uniform electric field. Solvated particles can respond to this force by either moving towards (positive DEP) or away (negative DEP) from the electrodes generating the electric field. The technique can be used to manipulate many biological particles, opening up new opportunities for nucleic acid based biosensing devices. I aim to develop a RNA hybridization probe functionalised on a microelectrode, capable of rapid detection and DEP based target sorting. The DEP collection and repulsion of ribosomal RNA and CdSe Quantum Dots on microfabricated interdigitated Au electrodes were observed using TIRF microscopy, and measured as a function of the strength and frequency of the applied electric field.

This is a weekly series of informal talks given primarily by members of the soft condensed matter and statistical mechanics groups, but is also open to members of other groups and external visitors. The aim of the series is to promote discussion and learning of various topics at a level suitable to the broad background of the group. Everyone is welcome to attend..

Find out more about Condensed Matter lunchtime seminars.