Intracellular gold nanoparticle aggregation and their potential applications in photodynamic therapy

Gold nanoparticles (Au NPs) with opposite surface charge can form aggregates through electrostatic interaction and exhibit surface plasmon resonance (SPR) induced-localized electromagnetic (EM) field enhancement under light irradiation. Intracellular aggregation of Au NPs can further improve the therapeutic efficiency of Au NP-enhanced photo-dynamic therapy of cancer by promoting singlet oxygen generation.