Abstract
The adhesiveness and stability of ubiquitously distributed biofilms is a significant issue in many areas such as ecology, biotechnology and medicine. The magnetic particle induction (MagPI) system allows precise determinations of biofilm adhesiveness at high temporal and spatial resolution on the mesoscale. This paper concerns several technical aspects to further improve the performance of this powerful experimental approach and enhance the range of MagPI applications. First, several electromagnets were built to demonstrate the influence of material and geometry with special regard to core remanence and magnetic strength. Secondly, the driving force to lift up the particles was evaluated and it was shown that both the magnetic field strength and the magnetic field gradient are decisive in the physics of the MagPI approach. The intricate combination of these two quantities was demonstrated with separate experiments that add permanent magnets to the MagPI system.
Acknowledgements
The authors are grateful for the contribution of the three bachelor students Alexander Kikillus (MagPI calibration), Thomas Bierbaum (experiment on magnetic gradient) and Christian Dany (SQUID measurements). They thank Rolf Reuter and Minh Vu for supporting the high precision balance and SQUID measurements, respectively.
Disclosure statement
No potential conflict of interest was reported by the authors.