Zhu Ming-Qiang, Zhu Linyong, Han Jason J, Wu Wuwei, Hurst James K, Li Alexander D Q
Department of Chemistry, Washington State University, Pullman, 99164, USA.
J Am Chem Soc. 2006 Apr 5;128(13):4303-9. doi: 10.1021/ja0567642.
Polymer nanoparticles of 40-400 nm diameter with spiropyran-merocyanine dyes incorporated into their hydrophobic cavities have been prepared; in contrast to their virtually nonfluorescent character in most environments, the merocyanine forms of the encapsulated dyes are highly fluorescent. Spiro-mero photoisomerization is reversible, allowing the fluorescence to be switched "on" and "off" by alternating UV and visible light. Immobilizing the dye inside hydrophobic pockets of nanoparticles also improves its photostability, rendering it more resistant than the same dyes in solution to fatigue effects arising from photochemical switching. The photophysical characteristics of the encapsulated fluorophores differ dramatically from those of the same species in solution, making nanoparticle-protected hydrophobic fluorophores attractive materials for potential applications such as optical data storage and switching and biological fluorescent labeling. To evaluate the potential for biological tagging, these optically addressable nanoparticles have been delivered into living cells and imaged with a liquid nitrogen-cooled CCD.
已制备出直径为40 - 400纳米的聚合物纳米颗粒，其疏水腔内掺入了螺吡喃 - 部花青染料；与它们在大多数环境中几乎不具有荧光特性相反，封装染料的部花青形式具有高度荧光性。螺 - 部光异构化是可逆的，通过交替照射紫外线和可见光可使荧光“开启”和“关闭”。将染料固定在纳米颗粒的疏水口袋内还提高了其光稳定性，使其比溶液中的相同染料更能抵抗光化学开关引起的疲劳效应。封装荧光团的光物理特性与溶液中相同物质的光物理特性有很大不同，这使得纳米颗粒保护的疏水荧光团成为光学数据存储与开关以及生物荧光标记等潜在应用的有吸引力的材料。为了评估生物标记的潜力，这些光学可寻址纳米颗粒已被递送至活细胞中并用液氮冷却的电荷耦合器件进行成像。
