Disposable Membrane Sensors for Biohazardous Substances Disposable Membrane Sensors

摘要

The concept of bilayer lipid membrane sensing is elaborated. Disposable bilayer lipid membrane sensors permit both stochastic and deterministic sensing regimes. Technology for membrane sensor preparation is described in details. Stochastic membrane sensing using ion channels is described. Detection of cyano-bacterial toxins in waters by means of a stochastic sensing (ion channel induction) reveals a signature for a particular toxin type. This signature is especially well revealed by using the method of current-voltage surfaces, which establishes a bridge between stochastic and deterministic sensing by applying a time-averaging procedure. Flexoelectricity of membranes provides another way of deterministic sensing, of a stimulus-response type. The flexoelectric response is modulated by adsorption of the analyte over the membrane surface. Detection of environmental pollution of waters by heavy metal ions (Cd~(++) and Hg~(++)) is thereby rendered possible. This approach is confronted with a stochastic sensing of the same metal ions by alteration of the channel open/closed probability and average channel current of two familiar channels, gramicidin and alamethicin.