| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 742438 | Sensors and Actuators B: Chemical | 2012 | 5 Pages |
Dimethyl methylphosphonate (DMMP) and Escherichia coli are mimics for chemical and biological agents, respectively. For designing robust sensor systems aiming at detecting them in real-life indoor environments, we designed artificial receptors based on bulk and surface imprinted polymers, respectively. Bulk-imprinted artificial recognition materials for DMMP yielded detection limits of 0.2 ppm in air on quartz crystal microbalance (QCM) sensor with selectivity factors of >40 towards indoor background contaminants, such as alcohols or acetic esters. The sensor layers retain their sensitivity for at least one year thus showing potential for maintenance-free long term sensing. They can be combined with pre-concentrator units to increase the overall performance of the system.Surface-imprinted polyurethanes optimized to selectively recognize E. coli showed ten times higher sensor responses on QCM than the respective non-imprinted polymers. Detection limits of these sensors turned out to be in the range of 0.1 mg/ml E. coli in aqueous solution. Different strains of this species (b and w, respectively) could be discriminated with selectivity factors of at least three thus implementing bioanalogous recognition in robust, man-made materials.
