A new type of optical nano-sensors has been suggested by young researchers from ITMO University. The working principle of the optical nano-sensors is founded on the interaction of light in thin films: a parallel effect can be seen in soap bubbles. Such sensors can be rapidly manufactured with an inkjet printer and special ink composed of titanium dioxide. At some point, the sensors can be used for speedy biomedical analysis. The results have been reported in Nanoscale.
Design of sensitive and low-cost sensors for biomedical study is one of the most crucial responsibilities in modern science. To solve it, ITMO University scientists aim to modify the working principle of a conventional printer. Using inkjet printing, researchers create advanced systems for sensing nano-objects.
The synthesis begins after a special ink containing titanium dioxide is ready. Using an inkjet printer, it is applied to a silicon substrate in the form of a film measuring 200-400 nm in thickness, which when compared with the human hair is hundreds of times thinner. As a result of this interference, the transparent film seems to be colored, and its color is subject to its thickness. Once a nanoscale object, be it a bacteriophage or a nanoparticle, is attached to the film surface, the thickness varies and so does the color. Using a specifically engineered scale for the film color assessment, researchers can learn how many nano-objects have rested on it and what size they are.
The developed sensor prototype can conduct quantitative as well as qualitative analysis, although it is still not selective. Researchers plan to restrain antibodies on the film surface to detect distinct proteins in biological samples.
We did a lot of preparation: designed the concept and studied a lot of literature. Since this method is based on a complex physical phenomenon, we not only worked as chemists, but also attempted to take into account the optical, technological and biological aspects. This way, we managed to solve a number of technical issues during the experiment: we selected the parameters of the film and the substrate and also adapted the previously developed ink. Our further work is aimed at adapting the developed system for the biomedical application of such sensor.
Anna Frosinyuk, Study’s First Author and Student, SCAMT Laboratory, ITMO University.