花菁树枝状大分子的合成与性质研究

Synthesis and Characterization of Cyanine Dendrimer

花菁染料因具有高荧光产率、高摩尔消光系数、狭窄的吸收/发射波段等优点,而被广泛用于荧光诊疗领域。但在实际应用中,存在稳定性差、易淬灭和光漂白等问题,而纳米技术可以克服这些弊端。采用发散合成法制备了一系列以七甲川花菁染料为核心分子、以生物相容性优异的赖氨酸为分支单元的荧光树枝状大分子。对其进行了结构和光学性能的表征,并初步探究了该荧光树枝状大分子在体外细胞中的成像能力。结果表明:合成得到的第一到第三代花菁树枝状大分子具有精准的化学结构,纯度较高,荧光强度、荧光量子产率及荧光寿命均随着代数的增加而增长,并显示出良好的细胞荧光成像的能力。

Cyanine dyes are widely used in the field of fluorescence diagnostic and therapeutical filed because of their high fluorescence yield,high molar extinction coefficient,and narrow absorption/emission bands.However,there are problems such as poor stability,easy quenching and photobleaching in applications,and nanotechnology can overcome these drawbacks.A series of fluorescent dendritic macromolecules with heptamethine cyanine as the core molecule and lysine with excellent biocompatibility as the branching unit were prepared by evanescent synthesis.The structural and optical properties were characterized,and the cell imaging ability of the fluorescent dendrimers was preliminarily investigated.The results showed that the synthesized first-to third-generation cyanine dendrimers had precise chemical structures,high purity,and the fluorescence intensity,fluorescence quantum yield and fluorescence lifetime increased with the increase of generations,and showed good ability of cell fluorescence imaging.