Magnetospirillum bacteria sensing using a microbubble WGM resonator.

In this study, hollow whispering gallery resonators were filled with an aqueous solution containing magnetospirillum magneticum (strain AMB-1) bacteria and the response to an external magnetic field was investigated. Magnetotactic bacteria can align with the field lines when exposed to a magnetic field. This changes the effective refractive index of the resonator and leads to shifts in the resonance frequencies of the whispering gallery modes, depending on the applied magnetic field strength. This work investigates the potential of a microbubble resonator platform for biosensing applications and the use of magnetotactic bacteria as a novel magnetic field-sensing substance.