Innovation Competition Prize for Cavendish Researchers

CamBridgeSens, the University of Cambridge's EPSRC funded network for sensor research, have just announced Innovation Competition grant winners of grants totaling more than £75K to benefit researchers at the University of Cambridge. Among the winners were Dr. Adrian Ionescu and Dr. Justin Llandro from the Cavendish working together with Dr. Nicholas Darton from the Department of Chemical Engineering and Biotechnology. They won £15K to fund research into “Magnetic Bacteria for Biosensor Applications”. Their multidisciplinary team also includes Dr. David Darling from the Department of Haemotological Medicine, Kings College London. Having already demonstrated promising results after the seed-funding from the CamBridgeSens Initiative, this team plans to extend their work using the prize to generate data for a major grant application.

Project description:
Chemically synthesised magnetic nanoparticles are currently used experimentally for magnetic labelling of biological entities. One of the drawbacks of using these particles is their inhomogeneous size and moment distribution. This inhomogeneity leads to a poor quantification of their response upon detection by current sensor technologies. Such sensors include those operating via magnetoresistance (MR) effects such as Tunnelling MR (TMR) and Giant MR, for which the 2007 Nobel prize in physics was awarded to Fert and Gruenberg.

The question arises whether or not magnetic nanoparticles naturally produced by magnetotactic bacteria have a more homogeneous particle distribution and therefore can be used to overcome this problem.

The first objective of our research was a thorough quantification of magnetic properties and size distribution of magnetic nanoparticles in bacterial cells. These characterisation studies included superconducting quantum interference device magnetometry and provided detailed information on the magnetic moment, anisotropy strength, size and size distribution of clusters of the biologically synthesised iron oxide nanoparticles.

As a second objective we proposed to sort magnetic bacteria by means of a microfluidic channel with an externally applied magnetic field. Ultimately a TMR sensor has been integrated into the microfluidic system for the purposes of cell counting and selection of the most magnetic strains.