T.E.S.T is a team competing in Sensus 2018, its university is the TU Eindhoven. For Sensus 2018, T.E.S.T. investigated the possibilities for creating a biosensor which is able to measure the concentration of Vancomycin. The full TRD can be found via this link
Particle Cluster Competition Assay
Vancomyocin antibodies are present, which bind to the free Vancomyocin in the sample. However these also bind to small magnetic particles coated with vancomyocin. More vancomyocin in the sample means less antibodies that bind to the magnetic particles. This causes less particle dimers to form, which can be measured.
The dimers are first formed by using a eternal magnetic field to mix up the sample. After all dimers are formed, a laser light is shone upon the sample while a rotating magnetic field is applied. This causes the dimers to rotate and scatter light differently depending on how the magnetic field is located relative to them. This scattered light is picked up with a photodiode that is positioned at 90 degrees from the laser. The dimer rotation frequency is then calculated by using a fast fourier transform.
A user interface is made where users can log into their own account, where they can see previous measurements, adjust settings for the magnet and send results via email. This is done through a touchscreen on the biosensor.