A challenge for theranostics: is the optimal particle for therapy also optimal for diagnostics?

Area of Science:

• Nanotechnology
• Biomedical Engineering
• Oncology

Background:

• Theranostics combines diagnostic and therapeutic capabilities.
• Nanoparticles offer advantages for drug delivery and in vivo imaging.
• Theranostic nanoparticles are promising for cancer treatment.

Purpose of the Study:

• Investigate the effect of gold nanoparticle (GNP) size on tumor uptake and imaging.
• Determine if optimal particle size for therapy aligns with optimal size for diagnostics.
• Evaluate GNPs for head and neck cancer theranostics.

Main Methods:

• Synthesized anti-EGFR conjugated GNPs of varying sizes (20-120 nm).
• Assessed GNP uptake in human squamous cell carcinoma cells (in vitro and in vivo).
• Evaluated tumor visualization using CT imaging.

Main Results:

• Nanoparticle size significantly influences in vivo activity.
• Highest tumor uptake observed with 20 nm GNPs.
• Optimal contrast enhancement achieved with 50 nm GNPs, not 20 nm.

Conclusions:

• The optimal nanoparticle size for drug delivery is not necessarily optimal for diagnostic imaging.
• Tailored nanoparticle design is crucial for effective theranostic applications.
• Further investigation into nanoparticle characteristics for theranostics is warranted.