Posted: Nov 02, 2010

Gold nanoparticles can induce luminescence in leaves

(Nanowerk News) Post-doctor Yen-Hsun Su of Research Center for Applied Science (RCAS), Academia Sinica, Taiwan, a former student of Department of Physics at National Cheng Kung University (NCKU) supervised by Prof. Wei-Min Zhang of Department of Physics and Assistant Prof. Shih-Hui Chang of Institute of Electro-Optical Science and Engineering, has discovered that gold nanoparticles can induce luminescence in leaves.
As this discovery has captured the attention of Royal Society of Chemistry, the largest organization in Europe for advancing the chemical sciences, the paper Dr. Yen-Hsun Wu has written has been accepted for publication in the journal Nanoscale and he has also been interviewed by the academic magazine Chemistry World.
Recently, Dr. Yen-Hsun Wu has returned to his alma mater to share the good news with Prof. Wei-Min Zhang and Assistant Prof. Shih-Hui Chang, and they have praised his outstanding research performance.
When Senior Executive Vice-President Da-Hsuan Feng is informed of this incident, he has found time to meet Dr. Yen-Hsun Wu, encouraged him to continue his research on the related fields and made a suggestion that Department of Physics and Department of Materials Science and Engineering should jointly organize workshops for the students to have a deeper understanding and knowledge of nanotechnology and bioluminescent science.
Assistant Prof. Shih-Hui Chang mentioned, "Light emitting diode (LED) has replaced traditional light source in many display panels and street lights on the road. A lot of light emitting diode, especially white light emitting diode, uses phosphor powder to stimulate light of different wavelengths. However, phosphor powder is highly toxic and its price is expensive. As a result, Dr. Yen-Hsun Wu had the idea to discover a method which is less toxic to replace phosphor powder which can harm human bodies and cause environmental pollution. This is a major motivation for him to engage in the research at the first place."
In his research, by implanting the gold nanoparticles into Bacopa caroliniana plants, Dr. Yen-Hsun Su was able to induce the chlorophyll in the leaves to produce a red emission. Under high wavelength of ultraviolet, the gold nanoparticles can produce a blue-violet fluorescence to trigger a red emission of the surrounding chlorophyll.
"In the future, bio-LED could be used to make roadside trees luminescent at night. This will save energy and absorb CO2 as the bio-LED luminescence will cause the chloroplast to conduct photosynthesis," said Dr. Yen-Hsun Su in the interview with the reporter from magazine Chemistry World.
Prof. Wei-Min Zhang, Assistant Prof. Shih-Hui Chang and Dr. Yen-Hsun Su have emphasized that the technologies and bioluminescence efficiency need to be improved for the trees to replace street lights in the future and reach the goal of energy saving and environmental protection.
In addition, Dr. Yen-Hsun Wu and Prof. Wei-Min Zhang have participated in an interview with a reporter from another international scientific magazine New Scientist, which is founded in 1956 and has covered features, news and commentaries on environmental issues such as climate change.
Source: National Cheng Kung University