Fukaminato Tuyoshi, Sasaki Takatoshi, Kawai Tsuyoshi, Tamai Naoto, Irie Masahiro
Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, Hakozaki 6-10-1, Higashi-ku, Fukuoka 812-8581, Japan.
J Am Chem Soc. 2004 Nov 17;126(45):14843-9. doi: 10.1021/ja047169n.
Photochromic reactions of diarylethene derivatives were detected at a single-molecule level by using a fluorescence technique. Fluorescent photoswitching molecules in which photochromic diarylethene and fluorescent bis(phenylethynyl)anthracene units are linked through an adamantyl spacer were synthesized, and switching of fluorescence upon irradiation with UV and visible light was followed in solution as well as on polymer films at the single-molecule level. Although in solution the fluorescence intensity gradually changed upon irradiation with UV and visible light, digital on/off switching between two discrete states was observed at the single-molecule level. The "on"- and "off"-times were dependent on the power of UV and visible light. When the power of UV and visible light was increased, the average on- and off-times became short in proportion to the reciprocal power of the light. The response-times were found to show distribution. The distribution of the on- and off-times is considered to reflect the difference in the micro-environment as well as conformation of the molecules.
通过荧光技术在单分子水平上检测了二芳基乙烯衍生物的光致变色反应。合成了光致变色二芳基乙烯和荧光双(苯乙炔基)蒽单元通过金刚烷基间隔基连接的荧光光开关分子,并在溶液以及聚合物薄膜上在单分子水平上跟踪了用紫外光和可见光照射时荧光的切换。尽管在溶液中,用紫外光和可见光照射时荧光强度逐渐变化,但在单分子水平上观察到了两种离散状态之间的数字开/关切换。“开”和“关”时间取决于紫外光和可见光的功率。当紫外光和可见光的功率增加时,平均开和关时间与光功率的倒数成比例地变短。发现响应时间呈现分布。开和关时间的分布被认为反映了分子微环境以及构象的差异。