Hide menu

Bio- and chemical sensing

Sensing interfaces and biomimetic membranes

We investigate here how the self-assembly technique can be used to design and develop novel sensing interfaces, as well as templates for sensing interfaces. A series of differently functionalized alkanthiolate SAMs have been prepared and tested using a surface acoustic wave (SAW) device for the development of a gas sensor for dimethylmethylphosphonate, a model molecule for the highly toxic sarin molecule.
We have also employed the nanoporous assemblies of thiocholesterol for the development of electrochemical sensing surfaces for studies of fast electron transfer kinetics and for detection of pharmaceutical compounds, like promazin. A class of cage molecules consisting of tert-butylcalix[4]arene entities, capable of forming inclusion complexes with small organic compounds (e.g. toluene), has been tested and charactrerized for sensing applications together with scientists from Eberhard-Karls Universität, Tübingen.

A considerable part of the sensing research is devoted to the deveopment of protein rejecting and biocompatible coatings. Sugar and polyethylene glycol-terminated SAMs are prepared and analysed in various biofluids in an attempt to identify the critical surface properties for obtaining layers with low non-specific binding. We investigate, for example, layers with controlled surface energy, tail group mobility, water binding capacity and morphology. This is a joint project with the chemistry department, at Linköping University and the biomaterials group at our laboratory. The group is also involved in a number of projects aiming at the development of efficient and reliable protocols for the immobilization of biologically complex recognition elements on 2-D and 3-D sensing interfaces. Attachment of receptors, peptides, proteins, antibodies, oligonucleotides and so forth are performed in collaboration with molecular biologists, farmacologists and biomaterial scientists.

Oligo(ethylene glycol) OEG-SAMs are also of interest for the development of a template for the attachment of lipid bilayer structures containg functional trans-menbrane proteins onto surfaces. The idea is to use the OEG layer as a flexible water reservoir between the electrode surface and the lipid bilayer. The OEG layer also ensures that the intracellular loops of  the transmembrane protein remains in a functional state. This project is conducted together with the Chemistry Department and detailed spectroscopical studies are undertaken in an attempt to broaden the understanding of the phase behaviour and water binding properties of OEG-SAMs. In the long run we hope to be able to attach lipid membrane structures on patterned surfaces for the development of multicomponent array sensors. Micro contact printing (uCP) is used to generate the patterned surfaces.

Responsible for this page: Erik Martinsson
Last updated: 05/16/06