Plasmonic Au@Ag Core-Shell Nanoisland Film for Photothermal Inactivation and Surface-Enhanced Raman Scattering...

Area of Science:

• Materials Science
• Nanotechnology
• Biomedical Engineering

Background:

• Plasmonic metal nanomaterials are crucial for biomedical sensing and treatment.
• Gold-silver core-shell nanoisland films (Au@AgNIFs) possess unique optical properties.

Purpose of the Study:

• To synthesize and characterize Au@AgNIFs for biomedical applications.
• To evaluate their efficacy in photothermal bacterial eradication and SERS detection.
• To explore their potential as a platform for bacterial theranostics.

Main Methods:

• Seed-mediated growth for Au@AgNIFs synthesis.
• Characterization using SEM, EDX, and AFM.
• UV-Vis spectroscopy for optical properties.
• Photothermal effect evaluation under simulated sunlight.
• Bacterial eradication assays for *E. coli* and *S. aureus*.
• Surface-enhanced Raman scattering (SERS) measurements.

Main Results:

• Au@AgNIFs exhibited broad visible light absorption due to surface plasmon resonance.
• Optimal Au@AgNIFs reached 66.9 °C under simulated sunlight, enabling photothermal bacterial eradication.
• Consistent photothermal effect observed during cyclic light exposure.
• Superior photothermal eradication efficiency against *E. coli* and *S. aureus*.
• Enhanced bacterial growth inhibition compared to bare glass.
• Validated as effective SERS substrates for bacterial signal amplification.

Conclusions:

• Au@AgNIFs are successfully synthesized and characterized.
• The developed nanomaterials demonstrate significant potential for photothermal therapy against bacteria.
• Au@AgNIFs serve as efficient SERS substrates for bacterial detection.
• The integration of photothermal therapy and SERS detection positions Au@AgNIFs as a promising platform for bacterial theranostics.