Study of magnetic fields for technological and bioanalytical applications

Project Description

Magnetophoresis describes the separation of magnetic entities from a sample matrix. Magnetic particles with tailored surface chemistry (chemical functional groups, antibodies, ssDNA) to bind molecules of interest are commonly used in biochemical and clinical analysis. They rely on the specificity of two phenomena. (i) Molecular recognition between the particle surface molecule and the target molecule allows the 'fishing' of the desired molecules or cells even out the of the most complex matrices including urine, blood and stool sample for clinical analysis, food samples for pathogen analysis and sold and water samples for environmental analysis. (ii) An external magnet can then selectively pull the magnetically susceptible particles with their cargo, allowing the removal of the complex sample matrix. Such analysis is commonly carried out in a manual fashion with test tubes and frequent washing and pipetting steps. In recent years, many researchers have published on miniaturised analysis platforms, so-called lab-on-a-chip platforms to enable automation and integration of these processes. Indeed, the group of Prof. Pamme at Hull has been among the leaders in this area, developing assays on trapped particles, assays on continuous moving particles, working with pathogen cells labelled with magnetic microparticles for food analysis and yeast and cancer cells labelled with magnetic nanoparticles for toxicity screening and fine-tuned cell separation, respectively. Prof. Pamme's group has also worked on the generation and manipulation of magnetic w/o and o/w droplets in lab-on-a-chip devices. In addition, diamagnetic repulsion forces have been explored in Prof. Pamme's group, i.e. the manipulation of polymer particles, native cells or droplets and bubbles within a paramagnetic surrounding medium. This research is often conducted on a trial and error approach with a basic understanding of magnetic forces, averaged over a complex magnetic field matrix and a basic understanding of magnetic susceptibility of the particles, cells and droplets. Prof. Sandulyak's team has developed a fundamental understanding and derived key equations to describe magnetophoresis and magnetic forces that describe this behaviour with more precision that current crude models. This has been tested on macrofluidic system.