A facile one-pot method to synthesize ultrasmall core-shell superparamagnetic and upconversion nanoparticles

Area of Science:

• Materials Science
• Nanotechnology
• Biomedical Engineering

Background:

• Core-shell nanoparticles offer unique properties for advanced applications.
• Iron oxide and lanthanide-doped fluoride nanoparticles are promising for biomedical uses.
• Developing multifunctional nanoparticles is crucial for theranostics.

Purpose of the Study:

• To synthesize ultrasmall core-shell Fe3O4@NaYF4:Yb3+/Er3+ nanoparticles.
• To investigate their bifunctional magnetic and upconversion luminescence properties.
• To evaluate their potential for biomedical applications.

Main Methods:

• One-pot thermolysis synthesis using oleylamine.
• Characterization using XRD, XPS, TEM, FT-IR, UC luminescence, and PPMS.
• Evaluation of magnetic and optical properties.

Main Results:

• Uniform nanoparticles with a mean size of 14.5 nm and excellent dispersibility were obtained.
• The nanoparticles exhibited superparamagnetic behavior with a saturation magnetization of 8.45 emu/g.
• Efficient upconversion luminescence was observed upon excitation with a 980 nm laser.

Conclusions:

• Ultrasmall Fe3O4@NaYF4:Yb3+/Er3+ nanoparticles possess dual magnetic and optical functionalities.
• These nanoparticles demonstrate potential for biomedical applications, including cancer diagnosis and therapy.
• The synthesis method provides a scalable route to bifunctional nanomaterials.