College of Optoelectronic Engineering, Shenzhen University , Shenzhen 518060, China.
Anal Chem. 2018 Feb 6;90(3):2170-2177. doi: 10.1021/acs.analchem.7b04511. Epub 2018 Jan 25.
The design of highly efficient drug carriers, and the development of appropriate techniques to monitor their mechanism of action and therapeutic effect, are both critical for improving chemotherapy. Herein, a polymeric nanoparticle, PAH-Cit/DOX (poly(allylamine)-citraconic anhydride/doxorubicin), was synthesized and used as a nanodrug system for the efficient delivery and pH-responsive release of doxorubicin (DOX) into cancer cells. The PAH-Cit/DOX nanoparticles were stable at physiological pH but effectively released DOX under weakly acidic conditions. The release efficiency was 90.6% after 60 h of dialysis in phosphate-buffered saline at pH 5.5. Confocal images showed the rapid movement of the drug from the cytoplasm to the nucleus, indicating the effective drug release MCF-7 cells. Notably, the combination of fluorescence lifetime imaging microscopy (FLIM) and phasor analysis (phasor-FLIM) provides an approach to monitor the dynamic change of DOX fluorescence lifetime in intercellular environments. Phasor-differentiated lifetime pixel intensity in FLIM images was quantified and used to evaluate the DOX release from nanocarriers, making it possible to detect the dynamics of intracellular release and transport of DOX.
高效药物载体的设计以及监测其作用机制和治疗效果的适当技术的开发，对于提高化疗效果都至关重要。本文合成了一种聚合物纳米粒子 PAH-Cit/DOX（聚（烯丙胺）-柠康酐/阿霉素），并将其用作纳米药物系统，以将阿霉素（DOX）高效递送至癌细胞并实现 pH 响应释放。PAH-Cit/DOX 纳米粒子在生理 pH 条件下稳定，但在弱酸性条件下能有效释放 DOX。在 pH 5.5 的磷酸盐缓冲盐水中透析 60 h 后，释放效率达到 90.6%。共聚焦图像显示药物从细胞质快速向细胞核移动，表明 MCF-7 细胞中药物的有效释放。值得注意的是，荧光寿命成像显微镜（FLIM）和相分析（phasor-FLIM）的组合提供了一种监测细胞间环境中 DOX 荧光寿命动态变化的方法。通过量化相区分寿命像素强度在 FLIM 图像中的分布，可以评估纳米载体中 DOX 的释放情况，从而可以检测 DOX 的细胞内释放和转运动力学。
