Spherical SAW devices with self-assembled lipopolymers for odor-sensing

The paper reports on development of a novel method for fabrication of highly sensitive spherical surface acoustic wave (Ball-SAW) devices for odor-sensing. The proposed method is based on functionalization of the Ball-SAW devices’ surface by means of chemisorption of self-assembled lipopolymers. Once functionalized, the devices’ surface can be further modified by means of physisorption of various lipid derivatives. More traditional techniques used for sensing-film deposition on Ball-SAW devices (such as AC electrospray) cause a considerable attenuation of the acoustic wave propagation after many circulations. The method proposed here is relatively simple and additional attenuation due to coating is negligible even if the amount of the coating is the same as that in the traditional technique. This makes for a significant enhancement of sensitivity to odorants as compared to the sensors coated with traditional techniques.