Magnetic Resonance Force Microscopy

The MRFM is an imaging instrument that measures the force between a permanent magnet, and the spin magnetization. It uses a microfabricated cantilever to detect the interaction force between a magnetic field gradient and spins in a sample. They are currently trying to create ultrasmall cantilevers to further improve MRFM. The new cantilevers will allow for a much farther depth perception (current ones are very limited in seeing below the surface)



Since most of my classmates are in BioSolid Mechanics, the explanation of how it works won't be complicated. The magnetic field gradient is defined from the tip at the end of the detector. It defines the spins(fields) that will be probed by the instrument, The resonance frequency of a spin is proportional to the magnetic field it experiences. Allows us to probe only those spins whose resonance frequency matches the frequency w_o of the applied rf field. In other words, the slice we made in whatever "body".

With this technique, we can obtain a volume resolution 100 million times finer than conventional MRI which is really awesome. We can image very small biological "machines" much finer than we use to.MRFM can be used to image interesting biological samples including virus particles, proteins, functions and complex molecule. This new imaging system can provide us more insight into functions that we couldn't otherwise know exactly what was occurring(juxtaglomerular granular cells and nephron regulation)

http://www.its.caltech.edu/~hammel/mrfmpch.html