Metasurface-enhanced infrared spectroscopy: From protein detection to ceils differentiation

Summary form only given. The ability to distinguish between different states of a given cell, as well as The ability to distinguish between different states of a given cell, as well as between different types of cells, is crucial for a variety of fundamental and clinical life sciences applications. Those include the monitoring of biochemical processes in a living cell and effective early cancer screening, to name just a few. The most common approach to differentiating between different cell types is immunological. However, the specificity of such approaches is limited because different cell types may over-express the same molecules. Therefore, there is.considerable interest in label-free approaches to distinguishing that relies entirely on the native properties of the cell, such as infrared spectroscopic cytology based on the quantification of vibrational fingerprints of cell's constituent molecules. Here we utilize a new experimental technique, Metasurface-Enhanced Infrared Spectroscopy (MEIRS), to interrogate the chemical composition of the cellular membranes. We utilize the strong field localization provided by plasmonic metasurfaces (see Fig.1a) to probe the outer region of the cell that is in the more intimate contact with the metasurface than the rest of the cell. The localization depth of the field, which is tens of nanometers (see Fig.1b), is comparable to the size of the cellular membrane.