Novel application of optical tweezers: colorfully showing molecular energy transfer

Approach could have applications for microchemistry, quantum dots

Visualizing Förster resonance energy transfer: Continuous laser irradiation causes Förster resonance energy transfer in the polymer droplet to accelerate, as seen in the changing color.

A novel technique with potential applications for fields such as droplet chemistry and photochemistry has been demonstrated by an Osaka Metropolitan University-led research group.

Professor Yasuyuki Tsuboi of the Graduate School of Science and the team investigated Förster resonance energy transfer (FRET), a phenomenon seen in photosynthesis and other natural processes where a donor molecule in an excited state transfers energy to an acceptor molecule.

Using dyes to mark the donor and acceptor molecules, the team set out to see if FRET could be controlled by the intensity of an optical force, in this case a laser beam. By focusing a laser beam on an isolated polymer droplet, the team showed that increased intensity accelerated the energy transfer, made visible by the polymer changing color due to the dyes mixing.

Fluorescence could also be controlled just by adjusting the laser intensity without touching the sample, offering a novel non-contact approach.

“Although this research is still at a basic stage, it may provide new options for a variety of future FRET research applications,” Professor Tsuboi explained. “We believe that extending this to quantum dots as well as new polymer systems and fluorescent molecules is the next challenge.”

The findings were published in Advanced Optical Materials.

Conflict of Interest

The authors declare no conflict of interest.


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Published: 24 Jun 2024

Contact details:

Rina Matsuki

3-3-138 Sugimoto, Sumiyoshi-ku,
Osaka 558-8585 JAPAN

Content type: 

Journal: Advanced Optical Materials
Title: Förster Resonance Energy Transfer Control by Means of an Optical Force
DOI: 10.1002/adom.202400302
Author(s): Tatsuya Nagai, Lu Jie, Satsuki Teranishi, Ken-ichi Yuyama, Tatsuya Shoji, Yuriko Matsumura, Yasuyuki Tsuboi
Publication date: 30 April 2024

Funding information:


The authors are grateful for the financial support of JSPS KAKENHI under Grant Numbers JP23H01794, JP20H02550, JP17K04974, JP18K14254, 16H06506/JP16H06507 for Scientific Research on Innovative Areas “Nano-Material Manipulation and Structural Order Control with Optical Forces,” “Molecular Engine” (JP19H05402), and “Revolution of Chiral Materials Science using Helical Light Fields” (JP23H04601). In addition, financial support from Sumitomo Electric Industry and The Canon Foundation is gratefully acknowledged.