Cantilever-based biosensors to help detect cancer antibodies

The biosensor could detect cancer biomarker antibodies to assist with developing cures for cancer 

SU8 Cantilever – second arm shows signs of thermal stress.

October 2011

Utilising a photoactive material, researchers at MCN and Deakin University are designing a cantilever based biosensor which detects cancer biomarker antibodies. The cantilevers are to be made from a photoactive material called SU8. MCN houses all the required tools under one roof that allows manufacture and testing of the complete cantilever device. Development so far has concentrated on two steps, photolithography and a special co-polymer layer.

The cantilever is created in two stages, a thin, 2µm  layer which forms the cantilever arm, and a thick, 100µm  layer which acts as the cantilever body, which are manufactured on silicon wafers. SU8 bonds to silicon so a co-polymer layer must be deposited onto the silicon surface in the MCNs reactive ion etchers, which forms a weak layer that allows the structure to be extracted from the silicon surface.

Development of these two stages is ongoing. After this the cantilevers will require a gold layer on the back to form a reflective surface required for subsequent characterisation steps. Prior to characterisation the devices will be taken to Deakin to have the surface functionalised to allow detection of cancer biomarker antibodies. Following this step the product will be returned to MCN to perform characterisation and verification within the biological atomic force microscope.