IBM working on 'DNA transistor'

The research effort is designed to demonstrate how a silicon based 'DNA Transistor' could help pave the way to read human DNA easily and quickly, in turn bringing advances in diagnosis and treatment. To move the work forward, IBM scientists specialising in nanofabrication, microelectronics, physics and biology are working out how to pass a DNA molecule through a 3nm wide hole – or nanopore – in a silicon chip. The molecule passes through the nanopore one unit of DNA at a time, allowing a sensor to 'read' the DNA. However, researchers are still working on quite what this sensor would look like. According to IBM, the challenge is to slow and control the motion of the DNA through the nanopore so the DNA structure can be read. Its researchers have developed a multilayer metal/dielectric nanostructure that contains the nanopore. Voltage biases between electrically addressable metal layers modulate the electric field inside the nanopore and the interaction of charges along the backbone of a DNA molecule with the modulated electric field trap DNA in the nanopore. By turning these gate voltages on and off, scientists have shown theoretically and computationally – and expect to prove experimentally – that it is possible to move DNA through the nanopore at a rate of one nucleotide per cycle – a rate that IBM scientists believe would make DNA readable.