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Samoorganizirane peptidne nanostrukture su obećavajući biomaterijal s velikim potencijalom u različitim biomedicinskim primjenama. Fluorescentno označavanje i oslikavanje stanica važna je metoda za praćenje različitih bioaktivnih molekula u živim sustavima, zahvaljujući izuzetnim prednostima, kao što su npr. jednostavna uporaba, visoka osjetljivost i visoka vremensko-prostorna rezolucija. U sklopu ove doktorske disertacije sintetiziran je niz fluorescentnih mono- (9a–d) i bis-pirenskih derivata (4a–c), a njihova fotofizička svojstva i svojstva samoagregacije u otopini istražena su UV/Vis i fluorescentnom spektroskopijom te dinamičkim raspršenjem svjetlosti (DLS). Piren je kromofor s izvrsnim fluorescentnim kvantnim prinosom i učinkovitom emisijom ekscimera što ga čini korisnim fluorescentnim senzorom. U polarnim otapalima (DMSO te smjesi otapala DMSO/voda) mono-pirenski derivati (9a–d) pokazaju karakteristike monomerne emisije, dok bispirenski derivati (4a–c) pokazuju emisiju monomera i ekscimera, pri čemu se isti može pripisati dinamičkom procesu. Proučavano je i ponašanje geliranja ovih spojeva te je samo za leucinski mono-pirenski derivat 9a otkriveno da pokazuje geliranje u aromatskim otapalima kao što su toluen i p-ksilen i u polarnoj smjesi otapala, voda/DMSO (4:1 v/v). Mono-pirenski derivati (9a–d) ne pokazuju citotoksični učinak na stanične linije A549 i RD. Skoro svi derivati, osim derivata 4b, pokazali su nakupljanje unutar živih i fiksiranih stanica, a makropinocitoza je utvrđena kao glavni put za ulazak derivata 4a u stanice., Self-assembled peptide nanostructures are very promising biomaterials with huge potential in several biomedical applications. Fluorescence imaging is emerging as promising and powerful means for monitoring various bioactive molecules in living systems, which is thanks to its remarkable advantages, such as easy operation, high sensitivity and high temporal-spatial resolution. As part of this doctoral dissertation series of fluorescent mono- (9a–d) and bis-pyrene derivatives (4a–c) were synthesized and their photophysical and self-aggregation properties in solution, were fully investigated by UV–vis and fluorescence spectroscopy and dynamic light scattering (DLS). Pyrene is a chromophore with excellent fluorescent quantum yield and efficient excimer emission that makes it useful as a fluorescence sensor. While in dilute DMSO mono-pyrene derivatives 9a– d show features characteristic of monomer emission, bis-pyrene 4a–c display both monomer and excimer emission, the latter attributable to a dynamic process. The gelation behaviour of these compounds was also studied, and only mono-pyrene leucine derivative 9a was found to display efficient gelation in aromatic solvents, such as toluene and p-xylene, and in polar solvent mixture, water/DMSO (4:1 v/v). Finally, mono-pyrene 9a–d showed no apparent cytotoxic impact on A549 and RD cell lines; almost all derivatives, except derivative 4b, showed accumulation within both live and fixed cells, and macropinocytosis was found to be the main pathway for derivative 4a to enter into the cells.