Qian Hongyun, Cheng Quan, Tian Youliang, Dang Huiping, Teng Changchang, Yan Lifeng
CAS Key Laboratory of Soft Matter Chemistry, Hefei National Laboratory for Physical Sciences at the Microscale, and Department of Chemical Physics, iCHEM, University of Science and Technology of China, Hefei, 230026, China.
J Mater Chem B. 2021 Mar 21;9(11):2688-2696. doi: 10.1039/d1tb00018g. Epub 2021 Mar 5.
Due to the hydrophobicity of the cyanine dye and the huge conjugated plane, the cyanine dye is prone to H-aggregation in aqueous solution, and the ultraviolet absorption is blue-shifted. Here, a hydrophilic quaternary stereo-specific cyanine (HQS-Cy) dye has been synthesized and polypeptide based nanoparticles have been prepared, which improve the water solubility of the cyanine in two aspects. First, at the molecular level, the sulfonic acid group increases the water solubility of the dye molecule while the dimethyl-ammonium functional group repels the molecule through the charge-charge interaction, destroying the planar characteristics of the cyanine structure, increasing the molecular distance between the dye molecules, and preventing the accumulation of cyanine. Secondly, at the nano-micelle level, the use of amphiphilic polypeptide blocks to encapsulate the dye increases the water solubility of the dye while also increasing its biocompatibility. The HQS-Cy@P NPs prepared by the above methods exhibit the maximum absorption at 985 nm and maximum fluorescence emission at 1050 nm in aqueous solution. HQS-Cy@P exhibits good photothermal stability and significant photothermal conversion efficiency of about 35.5%, and both in vitro and in vivo studies revealed that it is an efficient system for NIR-II imaging-guided photothermal therapy of cancer.
由于花菁染料的疏水性和巨大的共轭平面，花菁染料在水溶液中容易发生H-聚集，紫外吸收发生蓝移。在此，合成了一种亲水性季铵立体特异性花菁（HQS-Cy）染料，并制备了基于多肽的纳米颗粒，从两个方面提高了花菁的水溶性。首先，在分子水平上，磺酸基团增加了染料分子的水溶性，而二甲基铵官能团通过电荷-电荷相互作用排斥分子，破坏了花菁结构的平面特性，增加了染料分子之间的分子距离，防止了花菁的聚集。其次，在纳米胶束水平上，使用两亲性多肽嵌段包裹染料增加了染料的水溶性，同时也提高了其生物相容性。通过上述方法制备的HQS-Cy@P纳米颗粒在水溶液中在985 nm处表现出最大吸收，在1050 nm处表现出最大荧光发射。HQS-Cy@P表现出良好的光热稳定性和显著的光热转换效率，约为35.5%，体外和体内研究均表明它是一种用于癌症近红外二区成像引导光热治疗的高效系统。
