Nano Device for Monitoring Electrical Fluctuations on Bacteria Scale

摘要

This paper presents a nanowell device that detects the nano-scale electric field fluctuations due to ion cascade in bacteria. Solid-state nano devices allow for the measurement and analysis of fluctuation on the single cell or molecule scale, which can offer orders of magnitude higher sensitivity than microscopic measurements through conventional sensors. We fabricated a nanowell that is a 150nm wide gap in the middle of a titanium line on LiNbO3 substrate. The noise in the electrical current through this gap is measured. When bacteria are infected by bacteriophage, a large amount of ions are released, which yields spatiotemporal fluctuations of electric potential captured by this nanowell. It was demonstrated that this technology can be used to identify bacteria within minutes using the high specificity of phage/bacteria interaction. The perspective of building a biochip with hundreds of nano devices, immobilized phages and microfluidic channels so as to identify a large variety of bacteria is also discussed in this paper.