Monodispersed plasmonic Prussian blue nanoparticles for zero-background SERS/MRI-guided phototherapy

Area of Science:

• Nanotechnology
• Biomedical Engineering
• Materials Science

Background:

• Surface-enhanced Raman scattering (SERS) and magnetic resonance imaging (MRI) offer complementary advantages for cancer therapeutics.
• Current imaging techniques face limitations in spatial resolution and imaging depth.
• Developing multifunctional nanoparticles is crucial for integrated cancer diagnosis and therapy.

Purpose of the Study:

• To synthesize and characterize Prussian blue-encapsulated gold nanoparticles (Au@PB NPs) for dual-mode MRI and SERS imaging.
• To evaluate the potential of Au@PB NPs as contrast agents for in vivo imaging.
• To investigate the application of Au@PB NPs in combined photothermal (PT) and photodynamic (PD) cancer therapy.

Main Methods:

• Monodispersed Au@PB NPs were synthesized.
• The nanoparticles were characterized for their MRI contrast properties, utilizing the high relaxation efficiency of iron ions.
• SERS imaging capabilities were assessed, leveraging the plasmonic enhancement of the gold core on cyanide groups.
• Near-infrared absorption properties were evaluated for phototherapy applications.

Main Results:

• Au@PB NPs demonstrated excellent MRI contrast with high longitudinal (r1) and transversal (r2) relaxation efficiencies.
• The nanoparticles exhibited strong, stable, and specific SERS signals in the Raman-silent region, enabling subcellular-level imaging.
• Prussian blue's near-infrared absorption facilitated simultaneous photothermal and photodynamic therapy.
• The integrated nanoparticles provided zero-background SERS signals for accurate tumor navigation.

Conclusions:

• Au@PB NPs serve as a superior dual-mode contrast agent for MRI and SERS imaging.
• These nanoparticles are effective for in vivo tumor navigation and simultaneous PT/PD treatment.
• The developed nanoparticles represent a promising platform for image-guided cancer therapy.