Magnetic imaging of individual magnetotactic bacteria

Biotechnology represent a new and exciting application of SQUID microscopy. Several biomedical applications, such as bio-separation, MRI and drug delivery use nanomagnets. The magnetic properties of nanomagnets are usually measured in large groups, which can be problematic due to the large dispersion of their properties. Magnetotactic bacteria are a group of bacteria that naturally grow magnetic particles, which magnetically align along a chain and result in alignment of the bacteria with earth’s magnetic field (like a compass needle). We use scanning SQUID to detect magnetotactic bacteria and measure their moment properties and their response to small fields on an individual basis. We observe large dispersion in their magnetic properties.

With: Kathryn Moler, AC Matin  @Stanford