Deep tissue bio-imaging using two-photon excited CdTe fluorescent quantum dots working within the biological window

Area of Science:

• Biomedical Optics
• Materials Science
• Nanotechnology

Background:

• Deep tissue imaging is crucial for understanding biological processes.
• Current imaging techniques face limitations in penetration depth and resolution.
• Semiconductor quantum dots (QDs) offer unique optical properties for advanced imaging.

Purpose of the Study:

• To introduce a novel deep tissue imaging method using Cadmium Telluride (CdTe) semiconductor quantum dots (QDs).
• To demonstrate the feasibility of multiphoton excited fluorescence imaging at depths up to 2 mm.
• To explore the potential of CdTe-QDs for future thermal imaging applications.

Main Methods:

• Utilized 8 nm Cadmium Telluride (CdTe) semiconductor quantum dots (QDs).
• Employed two-photon absorption of 900 nm photons for excitation.
• Achieved 800 nm emission, falling within the biological window.
• Acquired deep tissue multiphoton excited fluorescence images.

Main Results:

• Efficient two-photon excitation of CdTe-QDs at 900 nm.
• High-resolution fluorescence imaging achieved at depths approaching 2 mm.
• Successfully obtained the first deep tissue multiphoton excited fluorescence image using CdTe-QDs.
• Demonstrated the thermal sensitivity of CdTe-QDs.

Conclusions:

• CdTe-QDs provide a viable platform for high-resolution deep tissue fluorescence imaging within the biological window.
• The developed method allows imaging at unprecedented depths (close to 2 mm).
• The thermal sensitivity of CdTe-QDs opens possibilities for future high-resolution deep-tissue thermal imaging.