The need for miniaturized and sensitive sensors for explosives detection is increasing in areas such as security and demining. Micrometer sized cantilevers are often used for label-free detection, and have previously been reported to be able to detect explosives. However, only a few measurements from 1 to 2 cantilevers have been reported, without any information on repeatability and reliability of the presented data. In explosive detection high reliability is needed and thus a statistical measurement approach needs to be developed and implemented. We have developed a DVD-based read-out system capable of generating large sets of cantilever data for vapor and liquid phase detection of 2,4-dinitrotoluene (DNT). Gold coated cantilevers are initially functionalized with tetraTTF-calixpyrrole molecules, specifically designed to bind nitro-aromatic compounds. The selective binding of DNT molecules on the chemically treated surfaces results in significant bending of the cantilevers and in a decrease of their resonant frequencies. We present averaged measurements obtained from up to 72 cantilevers being simultaneously exposed to the same sample. Compared to integrated reference cantilevers with non-selective coatings the tetraTTF-calixpyrrole functionalized cantilevers reveal a uniform and reproducible behavior.
- Explosives detection
- Cantilever sensor
- Optical read-out
Bosco, F., Bache, M., Hwu, E-T., Chen, C. H., Andersen, S. S., Nielsen, K. A., Keller, S. S., Jeppesen, J., Hwang, I-S., & Boisen, A. (2012). Statistical analysis of DNT detection using chemically functionalized microcantilever arrays. Sensors and Actuators B: Chemical, 171-172, 1054-1059. https://doi.org/10.1016/j.snb.2012.06.033