Dottorato in TECNOLOGIE DELL'INFORMAZIONE E DELLE COMUNICAZIONI (ICT)

Titolo della tesi: Sensors and Actuators for Lab-on-Chip Applications

This work presents three years of research activities regarding novel, original solutions for the treatment, movement and detection of biological material in Lab-on-Chip biomolecular analysis systems. In this framework, compact devices were developed to act as modules or sub-systems to be embedded in biosensing platforms and diagnostic chips, in the path of latest biomedical trends. Three main lines of investigations are reported in this field. Optical waveguides and thin-film photodetectors were engineered to produce an integrated waveguide sensor, aiming to interact with a biosample, and optically detect and quantify the concentration of a given analyte, with a working principle and an analysis methodology that are kept among the simplest with respect to the state of the art; moreover, the reported experimental results show noticeable sensing performances, competitive with currently established systems both in literature and on the market. Micro- and nano-electromechanical devices were thoroughly investigated, to enable enhanced biosample manipulation capabilities at the micro and nanoscale, profiting from unique and peculiar electromechanical features, and with the possibility to make a breakthrough in a wide spectrum of biomedical applications, such as nanosurgery-related fields. Also micro-sieving devices have been conceived with the aim to select the molecules to be analyzed, by filtering, sorting and separating particles inside inhomogeneous biological materials, such as blood of cell cultures. This research has been carried out with a multidisciplinary attitude, comprising electromechanics, optoelectronics, microfluidics, chemistry, biology. Microelectronic fabrication technologies were deeply investigated and extensively practiced to manufacture prototypes of the proposed devices. Experimental tests and proofs of concept were carried out to assess performances and to confirm their novelty and originality. The results are encouraging and assert them as promising tools in the biomedical field, with potential applications in blood analysis, food quality control, drug delivery, biological cells separation and selection, tissue engineering.