Abstracts

The study of new materials based on gellan gum (GG), a natural polysaccharide derived from bacteria, allows the production of modified and biocompatible hydrogels and films to suit different applications. In this work, GG was combined with network-forming molecules, such as sericin (SS), a protein extracted from silkworm cocoons aiming for a material with better optical and greater mechanical resistance. The SS material showed interesting mechanical and optical properties for a functional composite, with the ability to reproduce patterns on its surface film through the soft lithography process and periodic micropatterns with angle-dependent iridescent colors (Figure 1-left), structurally induced in the film by a mold, which aims applications such as sensors, random lasers, and structural color systems. Preliminary studies indicated reduced energy transfer rate between GG and lanthanide ions, which are important in the development of photonic devices due to their distinguished luminescent properties. The modified system, with sensitizing groups, was doped with Eu³⁺ showing an interesting sensitization effect (Figure 1-right), resulting in an increased emission intensity with longer lifetime of the excited state by the presence of SS. This effect enables these new materials to be studied as sensors printed on supports to produce intelligent packaging, either by suppression or enhancement of luminescence, for example.