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An Integrated System to Remotely Trigger Intracellular Signal Transduction by Upconversion Nanoparticle-mediated Kinase Photoactivation
Published on: August 30, 2017
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Tuning upconversion through a sensitizer/activator-isolated NaYF₄ core/shell structure.
Shuai Ye1, Guanying Chen, Wei Shao
1Key Laboratory of Optoelectronic Devices and Systems of Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, People's Republic of China. jlqu@szu.edu.cn.
Nanoscale
|February 12, 2015
Summary
Researchers developed core-shell upconversion nanoparticles (UCNPs) to tune emission colors. This novel sensitizer/activator-isolated structure offers new possibilities for UCNP applications in bioimaging and solar cells.
Area of Science:
- Materials Science
- Nanotechnology
- Photonics
Background:
- Tuning the emission color of upconversion nanoparticles (UCNPs) is crucial for expanding their applications.
- Conventional methods involve altering rare-earth ion types or concentrations.
Purpose of the Study:
- To introduce a new method for tuning UCNP emission colors using a core-shell structure.
- To investigate the impact of sensitizer/activator isolation on luminescence properties.
Main Methods:
- Fabrication of NaYF4 core-shell UCNPs with isolated sensitizer (Yb3+) and activators (Ho3+, Er3+, Tm3+).
- Characterization of luminescence properties and time-resolved spectra.
- Analysis of strain-induced modulation of emission channels.
Main Results:
- Core-shell structures converted typical green, yellow, and blue emissions to quasi-white, green, and pink-blue, respectively.
- Time-resolved spectra showed significant changes in decay lifetimes compared to co-doped UCNPs.
- Verified strain-induced modulation of emission channels.
Conclusions:
- Sensitizer/activator-isolated core-shell UCNPs provide a novel route to tune emission colors.
- This approach offers enhanced control over UCNP optical properties.
- These engineered UCNPs hold promise for advanced biophotonic and photonic applications.
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