Dimeric gold nanoparticle assemblies as tags for SERS-based cancer detection.

Area of Science:

• Nanotechnology
• Biomedical Imaging
• Materials Science

Background:

• Surface-enhanced Raman scattering (SERS) microscopy offers high sensitivity for molecular detection.
• Developing targeted probes for specific cell types remains a challenge in biomedical imaging.
• Nanoparticle clusters can enhance SERS signals through "hot spot" generation.

Purpose of the Study:

• To develop and characterize multifunctional nanoparticle probes for SERS-based tissue targeting and imaging.
• To engineer nanoparticle clusters with controlled gaps for optimal SERS enhancement.
• To evaluate the probes' efficacy in detecting glioblastoma cells.

Main Methods:

• Controlled assembly of gold nanoparticles into dimers (DNP-REP) using a Raman-active reporter (REP).
• Peptide functionalization of DNP-REP for targeted binding to living cells.
• Incubation of targeted DNP-REPs with cultured human glioblastoma cells.
• SERS mapping and comparison with confocal fluorescence imaging.

Main Results:

• Engineered DNP-REPs created narrow internanoparticle gaps, generating effective "hot spots" for SERS.
• Peptide-functionalized DNP-REPs demonstrated stability, controlled binding, and intracellular endocytosis in living cells.
• SERS maps of glioblastoma cells showed markedly enhanced signals compared to fluorescence, especially at low incubation times.
• High signal-to-noise ratio achieved even with a small number of internalized probes (40 DNP-REP).

Conclusions:

• The developed Raman reporter-based nanoparticle cluster probes are versatile for optical imaging.
• These probes enable fast, reliable, selective, and ultrasensitive tissue targeting.
• The technology shows promise for disease detection and screening applications.