Department of Organic Synthesis, University of Chemical Technology and Metallurgy, 8 Kliment Ohridsky Blvd., 1756 Sofia, Bulgaria.
Bioorg Med Chem. 2013 Nov 1;21(21):6292-302. doi: 10.1016/j.bmc.2013.08.064. Epub 2013 Sep 11.
Herein we report on the synthesis and sensor activity of a novel pH sensitive probe designed as highly water-soluble fluorescent micelles by grafting of 1,8-naphthalimide-rhodamine bichromophoric FRET system (RNI) to the PMMA block of a well-defined amphiphilic diblock copolymer-poly(methyl methacrylate)-b-poly(methacrylic acid) (PMMA48-b-PMAA27). The RNI-PMMA48-b-PMAA27 adduct is capable of self-assembling into micelles with a hydrophobic PMMA core, containing the anchored fluorescent probe, and a hydrophilic shell composed of PMAA block. Novel fluorescent micelles are able to serve as a highly sensitive pH probe in water and to internalize successfully HeLa and HEK cells. Furthermore, they showed cell specificity and significantly higher photostability than that of a pure organic dye label such as BODIPY. The valuable properties of the newly prepared fluorescent micelles indicate the high potential of the probe for future biological and biomedical applications.
本文报道了一种新型 pH 敏感探针的合成及传感活性，该探针通过将 1,8-萘酰亚胺-罗丹明双发色团 FRET 体系（RNI）接枝到具有明确两亲性嵌段共聚物-聚（甲基丙烯酸甲酯）-b-聚（甲基丙烯酸）（PMMA48-b-PMAA27）的 PMMA 嵌段上，设计成高度水溶性的荧光胶束。RNI-PMMA48-b-PMAA27 加合物能够自组装成胶束，胶束具有包含锚固荧光探针的疏水性 PMMA 核和由 PMAA 嵌段组成的亲水性壳。新型荧光胶束能够在水中用作高灵敏度的 pH 探针，并成功内化 HeLa 和 HEK 细胞。此外，它们显示出细胞特异性，并且比纯有机染料标记物（如 BODIPY）具有更高的光稳定性。新制备的荧光胶束的有价值性质表明该探针在未来生物和生物医学应用中具有很高的潜力。
