Highly selective sensor materials for discriminating carbonyl compounds in the gas phase using quartz microbalances

Host molecules of the dendrimer-type 1 and the oligolactam-type 2-4 are well suited to act as highly selective sensor layers for carbonyl compounds which allow to discriminate individual aldehydes and ketones. The host/guest effects are monitored via quartz microbalance (QMB). For this purpose, the receptors 1-4 were coated onto a surface of the QMB. When these devices come into contact with carbonyl compounds in the gas phase, reproducible signals are obtained within a short response time. Since the inclusion of the guests into the host is reversible, these sensors can be used in continuous fashion. The three macrocycles 2-4 studied show different host/guest selectivity despite their similar cavity sizes. (C) 1999 Elsevier Science S.A. All rights reserved.