RESUMEN
Gold nanorods (AuNRs) hold considerable promise for their use in biomedical applications, notably in the context of photothermal therapy (PTT). Yet, their anisotropic nature presents a notable hurdle. Under laser irradiation, these structures are prone to deformation, leading to changes in their optical and photothermal properties over time. To overcome this challenge, an efficient strategy involving the use of calix[4]arene-tetradiazonium salts for stabilizing AuNRs has been implemented. These molecular platforms are capable of irreversible grafting onto surfaces through the reduction of their diazonium groups, thereby resulting in the formation of exceedingly robust organic monolayers. This innovative coating strategy not only ensures enduring stability but also facilitates conjugation of AuNRs. This study showcases the superiority of these fortified AuNRs over conventional counterparts, notably exhibiting exceptional resilience even under sustained laser exposure in the context of PTT. By bolstering the stability and reliability of AuNRs in PTT, our approach holds the potential to drive significant advancements in the field.
RESUMEN
The interface robustness and spatial arrangement of functional molecules on metallic nanomaterials play a key part in the potential applications of functional nano-objects. The design of mechanically stable and electronically coupled attachments with the underlying metal is essential to bring specific desirable properties to the resulting hybrid materials. In this context, rigid multipodal platforms constitute a unique opportunity for the controllable grafting of functionality. Herein, we provide for the first time an in-depth description of the interface between gold nanorods and a chemically-grafted multipodal platform based on diazonium salts. Thanks to Raman and X-ray photoelectron spectroscopies and theoretical modeling, we deliver insights on the structural and electronic properties of the hybrid material. More importantly, it allows for the accurate assignment of Raman bands. The combination of experimental and theoretical results establishes the formation of four carbon-gold anchors for the calix[4]arene macrocycle leading to the exceptional stability of the functionalized nano-objects. Our results lay the foundations for the future design of robust and versatile platforms.