Suspended glass nanochannels coupled with microstructures for single molecule detection

We present a nonlithographic approach for forming free standing nanochannels, made of a variety of materials, that can be easily integrated with microfabricated structures. The approach uses a deposited polymeric fiber as a sacrificial template around which a deposited coating forms a tube. We formed suspended nanochannels of silica glass spanning a trench on a silicon wafer and used these structures for detection of single fluorescently labeled proteins. This geometry provides excellent isolation of the molecules of interest and also separates them from surrounding material that could create unwanted background fluorescence. The same geometry provides a platform for observing motion and mechanical response of the suspended nanochannel, and we measured the mechanical resonance of a glass channel of the type used for the fluorescent detection. This type of structure provides a general approach for integrating fluid carrying nanochannels with microstructures.