Combination Of Electrophoresis And Nanopore Sequencing Technology For Seeking A Biosensor For The Rapid Detection And Quantification Of Brett
A nanopore is a pore of nanometer size. It may, for example, be created by a pore-forming protein or as a hole in synthetic materials such as silicon or graphene. When a nanopore is present in an electrically insulating membrane, it can be used as a single-molecule detector. It can be a biological protein channel in a high electrical resistance lipid bilayer, a pore in a solid-state membrane or a hybrid of these – a protein channel set in a synthetic membrane. The detection principle is based on monitoring the ionic current passing through the nanopore as a voltage is applied across the membrane. When the nanopore is of molecular dimensions, passage of molecules (Brett and S. Cerevisiae) cause interruptions of the "open" current level, leading to a "translocation event" signal. The passage of some molecules through the membrane-embedded alpha-hemolysin channel (1.5 nm diameter), for example, can causes a ~90% blockage of the current (measured at 1 M KCl solution). Nanopore sequencing has been around since the 1990s, when Church et al. and Deamer and Akeson separately proposed that it is possible to sequence DNA using nanopore sensors. The concept is that if each base could produce different ionic current torrents during DNA translocating through a small channel (nanopore), then it would be possible to distinguish between different nucleotides. The pores are usually in a biological membrane, or in a solid-state film, that separates two compartments that contain conductive electrolytes. Electrodes are immersed in each compartment. The resulting electric field causes the electrolyte ions in solution to move through the pore through electrophoresis, generating an ionic current signal. When the pore is blocked, due to the passage of a biomolecule, the current flow is also blocked. You can determine the physical and chemical properties of the target molecules by analyzing the amplitude and duration of the blockades. The larger biomelecule will take a longer time to completely move over the nanopore.