Microcantilevers designed
for atomic force microscopy have been successfully used as
extremely sensitive chemical, physical and biological sensors. A
biosensor employs a biological or biochemical detector, which
can range from single proteins and enzymes up to whole cells and
microorganisms. In recent years, Biomolecules and their unique
ability of molecular recognition have been investigated in terms
of their mechanical response to external forces. One of the
latest efforts in this field has been to measure mechanical
responses of thin beams of silicon (microcantilevers) arranged
in a microfabricated array. This is achieved by coating one side
of these cantilevers with a sensor layer that shows an
individual response to analyte molecules. The intermolecular
forces arising from adsorption of these small analyte molecules
are known to induce surface stress, directly resulting in the
mechanical bending of cantilevers. Also, mass uptake of a
targeted analyte is reflected as a change in resonant frequency.
We can take advantage of biochemically induced cahnges to
directly and specifically transduce molecular recognition into
nano mechanical responses in a cantilever array.
Our work on cantilever array sensing is of direct interest to
Purdue's Center for Sensing Science and Technology (CSST).