Innovative Nanomaterials for Biomedical Applications: Photothermal Approaches for Antimicrobial Devices
Nosocomial infections, commonly known as hospital-acquired infections, present significant challenges within healthcare settings worldwide, particularly catheter-related infections (CRIs). With the rise of multidrug-resistant pathogens, alternative therapeutic strategies are urgently needed. In recent studies, light activated antimicrobial nanoparticle-polymer composites have shown promise in combating bacterial infections and addressing nosocomial challenges. Photothermal therapy (PTT), a novel approach utilizing the unique properties of noble metal nanoparticles, has emerged as a potential solution for selectively targeting and eliminating pathogenic microorganisms, including bacteria. This dissertation focuses on the application of PTT for combating catheter-related infections using nanoparticles. The research undertaken explores the synthesis, characterization, and functionalization of noble metal nanoparticles, specifically gold nanostructures, with diverse compositions and morphologies. These nanoparticles are embedded within a polydimethylsiloxane (PDMS) matrix to serve as models for biomedical devices, particularly catheters. The photothermal properties of the resulting films are extensively investigated to evaluate their effectiveness in achieving antibacterial effects. The first study presents the design of an adsorbate to mimic the surface properties of polydimethylsiloxane (PDMS), which serves as a compatibilizing agent in subsequent experiments. Additionally, the dissertation describes a method for incorporating gold-silver nanoshells (AuAgNShs) into the PDMS matrix. Under near-infrared (NIR) irradiation, the photothermal properties of the AuAgNShs-modified PDMS films exhibit rapid and efficient antibacterial activity. Furthermore, a comparative analysis is conducted between gold nanostar (AuNSts)-modified and AuAgNShs-modified catheter surfaces, evaluating their respective photothermal properties. The findings suggest that both AuAgNShs-modified and AuNSts-modified PDMS surfaces hold significant potential as therapeutic approaches for addressing catheter-related infections. These modified PDMS surfaces demonstrate promise in combating bacterial growth and might provide viable solutions to mitigate the challenges associated with nosocomial infections.