Caratterizzazione di bio-sensori cellulari multi-funzionali in diamante artificiale

Diamond, as both a source of power technologically advanced material and an object of beauty, is already a remarkably successful material in different areas. Its mechanical and thermal properties and its optical transparency and biocompatibility make it a perfect candidate for biosensing applications. The solid state group in Turin University is developing diamond based biosensors with which it is possible to perform in vitro measurements on neural and neuroendocrine cells. The possibility of using these biosensors to study the extracellular excitation mechanism is important to survey the action of drugs on neurons in the case of neurodegenerative diseases such as Alzheimer and Parkinson's. The goal of this thesis is to develop and characterise this biosensor and carry out biological measurement in both amperometry and potentiometry mode, getting chemical and electrical information from the same tissue. As described in the first part of this thesis work, the nanofabricated diamond was electrically characterized and it was afterwards assembled with the chip carrier. Subsequently, all the devices were functionally characterized with ciclic voltammetry, amperometry and impedance spectroscopy tests. The second part of the Thesis reports on the functionality of the device during biological acquisitions, i.e. in the detection of action potential and the firing rate of excitable cells and the ionic current due to cellular exocytosis.