In order to be able to optimize the decoration of bacteria with magnetic nanoparticles, we have developed a methodology for investigating the attachment of nanoparticles to the surface of bacteria by depositing a thin layer of the nanoparticles onto a Si(Ti)O 2 waveguide surface and measuring the bacterial (Rhodococcus erythropolis IGTS8) attachment kinetics under hydrodynamically controlled conditions. This is done by analysing the perturbation of the optical evanescent field generated by light guided along the substratum using optical waveguide lightmode spectroscopy (OWLS), with which the number of deposited particles and attached bacteria could be precisely and accurately determined. Despite the strong attachment implied by the positive surface charge of the nanoparticles and the negatively charged surface of the bacteria, the bacteria are initially attached reversibly. A criterion for ensuring that mixing of the nanoparticles and the bacteria is prolonged sufficiently for effective decoration to take place is proposed.
- Magnetic Nanoparticles
- Optical Waveguide Lightmode Spectroscopy
ASJC Scopus subject areas
- Biomedical Engineering