Study of Optical and Thermoplasmonic Properties of Silica‐Core/Gold‐Shell Nanoparticles Integrated within Cell Organelles: A Finite Element Method

Abstract

Photothermal therapy (PTT) using gold nanoparticles (GNPs) represent a promising innovation in biomedical treatment. Due to their unique optical properties, particularly surface plasmon resonance (SPR), gold nanoparticles can be activated by light to selectively destroy harmful cells, such as cancer cells, through heat generation. To enhance thermoplasmonic performance, gold nanoparticles can be combined with dielectric materials like silica (SiO₂) to form core/shell nanoparticles (). These structures show superior light‐to‐heat conversion compared to pure Au nanospheres, offering less invasive and more efficient cancer therapies. In this study, using the Finite Element Method (FEM), the optical and thermoplasmonic behavior of nanoparticles embedded in various subcellular locations—lysosome, membrane, mitochondria, nucleus, cytoplasm, and extracellular medium is investigated. It is analyzed how structural parameters like core radius and shell thickness affect surface plasmon resonance‐induced absorption and resulting heat generation. To evaluate their photothermal efficiency, the absorption efficiency, electric field enhancement, and local temperature rise are computed. These findings show that the optical and thermal responses of nanoparticles are strongly influenced by both nanoparticle structure and cellular localization. Notably, by tuning nanoparticles geometry and choosing appropriate target organelles, one can optimize laser parameters and thermal output, enabling highly effective and customizable photothermal therapy strategies for cancer treatment.