利用聚合物自组装实现绿色荧光蛋白生色团的荧光增强

根据绿色荧光蛋白的发光原理,采用聚乙二醇与聚甲基丙烯酸甲酯的两亲性两嵌段聚合物通过自组装包覆生色团的方式,模拟了绿色荧光蛋白发光,考察了组装行为对光学性能的影响,并将其用于细胞成像.通过核磁共振、高分辨质谱、傅里叶变换红外光谱、凝胶渗透色谱、紫外-可见吸收光谱及荧光光谱等表征了生色团分子和聚合物的结构及性能.生色团紫外最大吸收在371 nm,荧光最大发射峰在428 nm.聚合物和生色团进行组装后,其紫外吸收消失,而最大荧光发射峰强度大大增强,且发生了约70 nm的红移,这是因为组装使得生色团的自由旋转受到了限制,且生色团共平面性增加.动态光散射(DLS)和透射电镜(TEM)证明了纳米粒子的结构和尺寸.由于尺寸适合且具有较好的荧光性能,纳米粒子成功应用于细胞成像.这种绿色荧光蛋白生色团的简单自组装方式在生物成像领域具有良好应用前景.

FLUORESCENCE ENHANCEMENT OF GFP CHROMOPHORE THROUGH POLYMERIC SELF-ASSEMBLY

The fluorescence enhancement of green fluorescence protein(GFP) chromophore was realized through the self-assembly of amphiphilic block polymer and GFP chromophore.GFP chromophore and a series of amphiphilic poly(ethylene glycol)-b-poly(methyl methacrylate)(PEG-b-PMMA) with different PMMA lengths were synthesized.1H and 13C nuclear magnetic resonance(1H and 13C-NMR),high-resolution mass spectroscopy(HRMS),Fourier transform infrared spectroscopy(FTIR),gel permeation chromatography(GPC),ultraviolet-visible absorption(UV-Vis) and fluorescent spectroscopy were applied to study the structure and properties of chromophore and polymers.The maximum UV-Vis absorption peak and fluorescent emission peak were at about 371 nm and 428 nm,respectively.After the self-assembly of PEG-b-PMMA with chromophore,the UV-Vis absorption of chromophore disappeared while the fluorescent emission intensity increased markedly with a red-shift of 70 nm,which could be attributed to the chromophore's rotation restriction in polymeric nanoparticles.The size and shape of nanoparticles were measured by dynamic light scattering(DLS) and transmission electron microscopy(TEM).Benefiting from the appropriate size and good fluorescent property,these PEG-b-PMMA/chromophore nanoparticles were used in cell imaging successfully.