Recent advances in nanotechnology have made it possible to use carbon nanotubes as high-gain single-molecule sensors in Lab-on-a-Chip (LOC) microarray units. More specifically, directed single point defects can be created to design a binding site on the nanotube. The binding of a single molecule (e.g., DNA, RNA) to this single site modulates the conductance of the nanotube to a measurable extent, leading to a very highly specific sensitivity. For example, a measured change in the nanotube's conductance due to a bound single-stranded DNA is sensitive enough to detect the presence of a complementary DNA target. This nano-scale detection system is called a single-molecule field-effect transistor (smFET). By creating an array of smFETs with different probes attached to each nanotube, this will allow for the development of an LOC microarray the size of a USB memory stick.
This microarray platform has the potential to deliver qPCR levels of sensitivity without amplification, while delivering the degree of multiplexing characteristic of current DNA microarray technology. This method uses transduction (which is label-free), further simplifying sample preparation protocols by eliminating the need to design florescent labels, which is commonly used in current methods. This transduction approach allows arbitrarily low levels-of-detection (single molecule level) to be achieved, limited only by "incubation" times. By integrating this system with a complementary metal-oxide semiconductor (CMOS) integrated circuit, this LOC microarray can provide the detection of 500 unique nucleic acid sequences on a portable unit the size of a USB memory stick.
The concept of this technology has been demonstrated using thermodynamic and kinetic studies of DNA hybridization published in Nature Nanotechnology.
Patent Pending (WO/2013/158280)
Patent Pending (WO/2013/154750)
Tech Ventures Reference: IR CU12289