Intercoupling surface plasmon resonance and diffusion reflection measurements for real-time cancer detection

Area of Science:

• Biomedical Optics
• Nanotechnology
• Cancer Diagnostics

Background:

• Spatial diffusion reflection (DR) measurements using gold nanorods (GNR) offer a sensitive, non-invasive approach for real-time cancer detection.
• The spectral red-shift (Δλ) of GNRs is a key indicator that can be leveraged for enhanced detection capabilities.

Purpose of the Study:

• To demonstrate that wavelength-dependent DR measurements can observe spectral red-shifts in highly concentrated GNRs.
• To investigate the correlation between GNR concentration, spectral red-shift, and DR profiles for tumor detection.

Main Methods:

• Conjugating targeting moieties to GNRs to achieve specific accumulation in cancer cells.
• Utilizing dark-field microscopy to measure spectral red-shift (Δλ) in vitro at varying GNR concentrations.
• Performing double-wavelength DR measurements on tissue-like phantoms and tumor-bearing mice with different GNR concentrations.

Main Results:

• Observed spectral red-shift (Δλ) in concentrated GNRs due to inter-particle plasmon resonance.
• Demonstrated a direct correlation between the DR profile of concentrated GNRs and their spectral extension/red-shift.
• Validated the method in tissue-like phantoms and in vivo tumor models.

Conclusions:

• Wavelength-dependent DR measurements effectively detect spectral red-shifts in GNRs.
• The DR profile provides a reliable indicator of GNR concentration and spectral changes.
• This method holds significant potential as a tool for real-time superficial tumor detection.