Compuestos emisivos de Pt(II) e Ir(III) con aplicaciones biológicas y en iluminación de estado sólido

Resum

In the last decades, the interest in developing new luminescent organometallic compounds for possible applications, among others, in the field of biomedicine or in solid-state lighting (SSL) devices, has focused on the design of new Pt(II) and Ir(III) cyclometallic complexes. The biological and characteristics properties of the emissive states of these compounds can be easily modulated by ligand modification. To this end, this PhD thesis focuses on the synthesis, characterisation and study of the optical and biological properties (in collaboration with the Centro de Investigaciones Biomédicas de La Rioja-CIBIR) of emissive Pt(II) and Ir(III) compounds with cyclometallated groups derived from 2- phenylpyridine. Thus, this work presents a series of compounds of the [Pt(C^N)(C6F5)(L)] type (L = DMSO or bioactive phosphines), showing that the presence of phosphines with carboxylic groups enhances the cytotoxic activity, probably associated with the inhibition of tubulin microtubules. On the other hand, the work also present the synthesis of cationic complexes of stoichiometry [Ir(C^N)2(N^N)]+, which has been especially designed for their use in the biological field, or their integration into LECs. In order to obtain good compatibility with cellular media and modulate lipophilic properties, these compounds have been functionalised at the C^N group (with aldehyde or acid groups), at the bipyridine ligand (with amide -CONR or acid –COOH organic rests) or, indeed, at the counterion (Cl- or PF6-). For these complexes, it is also described their cytotoxic activity against two tumoral cell lines, both under normal (dark) conditions and their marked enhancement under blue light photoirradiation. Finally, the work describes the optical properties of Ir(III) derivatives bearing bipyridines functionalised with long organic chain amides (N^N = dbbpy, dobpy, ddobpy, dhbpy and dPEGbpy). These compounds have been designed with the aim of acting as emisors in environmentally friendly LECs. Thus, in collaboration with Dr. Ruben Costa at the Technical University of Munich, the derivative [Ir(dfppy)2(dbbpy)]PF6 has been incorporated into devices using cellulose acetate (CA) as biogenic electrolyte. These devices show higher stability, luminance and efficiency compared to reference devices without CA as electrolyte.