| Title: | Cavities generated by self-organised monolayers as sensitive coatings for surface acoustic wave resonators |
| Author(s): | Lieberzeit P; Greibl W; Jenik M; Dickert FL; Fischerauer G; Bulst WE; |
| Address: | "Department of Analytical Chemistry and Food Chemistry, University of Vienna, 1090, Vienna, Austria" |
| DOI: | 10.1007/s00216-006-0978-0 |
| ISSN/ISBN: | 1618-2642 (Print) 1618-2642 (Linking) |
| Abstract: | "Silanisation of quartz substrate surfaces with a mixture of two chlorosilanes, namely trimethylchlorosilane and 7-octenyldimethylchlorosilane, leads to sensitive coatings for volatile organic compounds (VOC) on surface acoustic wave (SAW) devices. In this way we created monolayers of molecular cavities engulfing the analytes according to host-guest chemistry directly on the device surfaces, and also confirmed the occurrence of such cavities by molecular modelling. We monitored the binding process of the silanes by using Fourier transform infrared (FTIR) spectrometry and atomic force microscopy (AFM). In order to increase the stiffness of the cavities, we crosslinked the terminal double bonds of the long spacers by heating the surface in the presence of a radical initiator. Compared to SAW delay lines silanised with trimethylchlorosilane, devices modified with the binary silane mixture lead to substantially higher frequency shifts when exposed to solvent vapour streams. Nearly instantaneous responses can be observed, which e.g. allows xylene detection down to a few ppm" |
| Notes: | "PubMed-not-MEDLINELieberzeit, Peter Greibl, Wolfgang Jenik, Michael Dickert, Franz L Fischerauer, Gerhard Bulst, Wolf-Eckhart eng Germany 2006/11/25 Anal Bioanal Chem. 2007 Jan; 387(2):561-6. doi: 10.1007/s00216-006-0978-0. Epub 2006 Nov 24" |
