The present review describes the fundamental chemistry of molecular recognition of ionic and neutral species at membrane surfaces, resulting in transmembrane signalling involving tansduction and in some cases, amplification of signals. Especially, the following modes of signal transduction/amplification will be focused. (i) Controlled flux of a large amount of ions through ordered membranes , (ii) active (uphill) transport through liquid membranes, and (iii) charge separation at the

more »

... d and solid/liquid interfaces. Some new chemical sensors have been fabricated by using different types of membranes, i.e., Langmuir-Blodgett membranes containing synthetic hosts as receptors . bilayer lipid membranes containing actual biological proteins (ion-channel and active transport proteins) , liquid membranes containing synthetic hosts as carriers , and inorganic single-crystal solid membranes. The principle and unique feature of the sensors based on these novel sensing membranes are also demonstrated.