Michael Berger over at Nanowerk is reporting on a nanomechanical sensor for the detection of cholera developed by scientists at Northwestern University and University of Illinois at Urbana-Champaign. The system utilizes synthetic membrane models called nanodiscs and cantilevers on a nano scale to perform the sensing.
A snippet from Nanowerk:
Nanomechanical sensors based on microcantilevers have emerged and gained increasing attention as a sensitive and label-free detection platform for a wide range of chemical and biological interactions. These microcantilever look a bit like tiny springboards (about 500 µm long and sometimes less than 1 µm thick) and they bend in response to different forces. Coating one side of such a microcantilever with a layer of high affinity receptors can transduce the binding of target molecules into a nanomechanical response of the cantilever (basically making the ‘springboard’ vibrate, albeit only by hundreds of nanometers).
When the cantilever signal transduction platform operates in the static deflection mode, the cantilever’s response to such a binding event is deflection in the range of a few to hundreds of nanometers as a result of the adsorption-induced surface stress and consequently the development of a bending moment. This cantilever deflection can then be measured either optically (using lasers) or electrically (by using piezoresistive or MOSFET-embedded microcantilevers).
Although the microcantilever detection platform provides sensitive transduction of specific molecular binding into the nanomechanical cantilever response in real-time, creating a robust and efficient receptor layer on the cantilever surface has remained a challenge.