Interfacing nanomaterials and biological systemsdevelopment and applications

Resumo

Nanomaterials (NMs) present uniquely physical, chemical and mechanical properties that made them very interesting for biological applications. Their interface with biological systems results in a synergistic combination that provides new properties and applications that surpass their individual components. These hybrids systems that combine biotic-abiotic entities, take advantage of the physicochemical properties and sensing capabilities of the NMs, and the biological properties of living cells as their programmable gene expression, self-replication and movement. FunNanoBio group (former Colloid Chemistry group) and Synthetic Biology group, where this thesis was carried out, are focused on the synthesis of nanoparticles with well-defined and tunable optical properties, and the engineering of biological systems respectively, aiming the development of novel hybrid systems with improved capabilities. In this thesis, we focus on the applications of noble metal nanoparticles, upconversion nanoparticles (UCNPs) and polymeric nanoparticles and their interface with different biological systems for generating biosensors, optogenetic actuators and bioimaging tools. The thesis is structured into five chapters. Chapter 1 gives a general introduction; chapter 2 describes intimin display system of human lectins in E.coli; chapter 3 aims to generate hybrid systems based on gold nanoparticles and bacterial cells through protein-protein interactions; chapter 4 is dedicated to UCNPs as light sources for optogenetic approximations and chapter 5 deals with the biofunctionalization of gold nanocapsules to obtain highly efficient SERS tags for multiplex detection of cell surface biomarkers. This thesis is expected to contribute to a better understanding of the huge possibilities at the interface between nanomaterials and biological systems and the further development of novel applications.