| Abstract [eng] |
With cancer progressing and evolving in highly complex mechanisms, it is crucial to research and evolve effective therapy and diagnostics strategies. Traditional therapy is of low specificity and has many side effects, so new generation therapy strategies, such as PDT, can be a promising alternative. PDT is characterized by high specificity and low background toxicity, while its effectiveness greatly depends on the depth of the tumor and ability of light to reach the photosensitizer accumulated there. NIR can penetrate deeper into tissues but lack energy to excite photosensitizers. UCNPs can offer a solution to this problem by converting NIR light into higher energy VIS - UV photons, that are capable to excite PS molecules. The goal of this study is to create multimodal theranostics platforms of personalized biological compounds, enriched with photosensitizer properties and upconverting mechanisms. Gold nanoclusters were synthesized by reducing chloroauric acid in alkaline human blood serum environment. The resulting Rh-AuNC were subsequently combined with Ce6 and UCNPs, forming initial multimodal theranostics complexes. Optical analysis of Rh-AuNC synthesis products characterized their photophysical properties and evaluated their stability through time. Based on that, Rh-AuNC were determined as suitable for further complexation with Ce6 and UCNPs. Protein-decorated AuNC interactions with Ce6 were evaluated. Results showed stronger interaction between BSA and Ce6, but Rh-AuNC-Ce6 complexes were also successfully formed. FL anisotropy of Rh-AuNC-Ce6 complexes allowed to determine the optimal rate for components as 1:4. Further enrichment with UC properties was achieved with UCNPs. This allowed for energy transfer in the complex, when NIR excited UCNPs emitted a VIS photon, which subsequently excited Ce6 molecules. This study shows the possibility to form multimodal theranostics systems from human blood plasma decorated AuNC, Ce6 and UCNPs. This complex achieved promising energy transfer capabilities and potentially, after further research, could be used for theranostics. |
