Photoactivated Nanoscale Temperature Gradient Detection Using X-ray Absorption Spectroscopy as a Direct...

Area of Science:

• Materials Science
• Nanotechnology
• Biomedical Engineering

Background:

• Nanoparticle-mediated thermal treatments offer a localized anticancer strategy with high efficacy.
• These nanoparticles generate heat, triggering therapeutic responses at cellular and tissue levels, sometimes without global temperature increases.
• Precise local temperature determination is vital for optimizing thermal onset and minimizing toxicity in nanotherapeutic strategies.

Purpose of the Study:

• To describe an experimental procedure for accurately inferring local temperatures of nanoparticles.
• To validate the methodology using gold-based nanoparticles and nanocrystals under laser photoexcitation.
• To demonstrate the potential for extending this nanothermometric approach to other nanosystems.

Main Methods:

• Utilized X-ray absorption spectroscopy (XAS) for direct and accurate temperature inference.
• Applied the method to gold-based nanoparticles, including single and hybrid nanocrystals.
• Investigated nanoparticle temperature under laser photoexcitation conditions.

Main Results:

• Successfully inferred local temperatures of nanoparticles with high accuracy.
• Revealed significant nanothermal gradients around the nanoheaters.
• Demonstrated the temperature-dependency of atomic parameters in nanoparticles.

Conclusions:

• X-ray absorption spectroscopy provides a robust method for nanothermometry.
• This technique allows for precise local temperature determination, crucial for optimizing nanoparticle-based thermal therapies.
• The methodology is adaptable to various nanosystems undergoing remote hyperthermal conditions.