Plasmonics and super-hydrophobicity: A new class of nano-bio-devices

Early detection of diseases has great importance in terms of success of the disease treatment. In fact, it has a profound positive influence on the response provided by the patient, leading to shorter and less invasive treatment regimes. We consider here the Raman detection of low (atto-molar) concentrates of molecules by applying nanofabrication techniques in the fabrication of plasmonic devices ful-filling the requirement of superhydrophobicity. Plasmonic resonances will have the effect of substantially increasing the local electric field around the fabricated nano-device which, in turn, will positively affect the Raman signal. Similarly, the superhy-drophobicity will play the crucial role in localizing the few molecules of the analyte around the plasmonic device, therefore allowing their detection in a manner other-wise impossible in diffusion-based devices. We will theoretically explain the concept of superhydrophobicity by providing also a roadmap for defining the optimal super-hydrophobic device, then we will introduce the fabrication process to realize such a device and, finally, we will provide the Raman counting of a series of analytes together with electromagnetic simulations illustrating the role of the electric field in the formation of the Raman signal.