Laboratory of Cellular Dynamics, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany.
J Am Chem Soc. 2013 Feb 27;135(8):3208-17. doi: 10.1021/ja3117813. Epub 2013 Feb 13.
A photomodulatable amphiphilic polymer has been synthesized with a backbone of poly[isobutylene-alt-maleic anhydride] and pendant dodecyl alkyl chains, Lucifer Yellow (LY) fluorescent probes, and diheteroarylethenes photochromic (PC) groups. The latter serve as reversible UV-activated FRET acceptors for the LY donors. We characterized the spectral and switching properties of the polymer in an organic solvent (CHCl(3)). In an aqueous medium the polymer forms polymersomes, constituting fluorescence probes ~75 nm in diameter. Self-assembly of the polymer on the surface of a quantum dot (QD) serving as a template creates a dual-color photoswitchable nanoparticle (psNP) with improved properties due to the increase in polymer density and efficiency of PC photoconversion. The psNP exhibits a second QD red emission band that functions as an internal standard requiring only a single excitation wavelength, and is much reduced in size (<20 nm diameter) compared to the polymersomes. The QD template also greatly increases the depth of modulation by photochromic FRET of the LY emission monitored by both steady-state and time-resolved (lifetime) fluorescence (from 20%→70%, and from 12%→55%, respectively).
一种光可调节的两亲聚合物已被合成，其主链为聚[异丁烯-alt-马来酸酐]和侧链十二烷基链，以及 Lucifer Yellow（LY）荧光探针和双杂芳基乙烯型光致变色（PC）基团。后者作为 LY 供体的可逆 UV 激活的 FRET 受体。我们在有机溶剂（CHCl3）中对聚合物的光谱和开关特性进行了表征。在水介质中，聚合物形成聚合物囊泡，直径约为 75nm。聚合物在作为模板的量子点（QD）表面上的自组装创建了一种双色光可切换纳米颗粒（psNP），由于聚合物密度和 PC 光转化效率的提高，其性能得到了改善。psNP 显示出第二个 QD 红色发射带，作为内部标准，只需要单一的激发波长，并且与聚合物囊泡相比，其尺寸大大减小（<20nm 直径）。QD 模板还大大提高了通过光致变色 FRET 监测的 LY 发射的调制深度，通过稳态和时间分辨（寿命）荧光（分别从 20%→70%和从 12%→55%）。
