To improve the potency of Heptamethine cyanines (Hcyanines) in cancer research, we designed and synthesized two novel Hcyanines based theranostic probes, IR794-Morph and IR794-Morph-Mpip, to enhance cancer cell internalization and targeting. In acidic conditions that resemble to tumour environment, both IR794 derivatives exhibited broad NIR absorption band (704‒794 nm) and fluorescence emission (798‒828 nm) that is suitable for deep seated tumour imaging. Moreover, in vitro study revealed that IR794-Morph-Mpip exhibited better cancer targetability towards various cancer cell lines under physiological and slightly acidic conditions compared to normal cells. IR794-Morph-Mpip was fast internalized into the cancer cells within the first 5 min and mostly localized in lysosomes and mitochondria. In addition, the internalized signal was brighter when the cells were in the hypoxic environment. Furthermore, cellular uptake mechanism of both IR794 dyes, investigated via flow cytometry, revealed that endocytosis through OATPs receptors and clathrin-mediated endocytosis were the main routes. Moreover, IR794-Morph-Mpip, displayed anti-cancer activity towards all tested cancer cell types with IC₅₀ below 7 μM (at 6 h incubation), which is approximately three times lower than that of the normal cells. Therefore, increasing protonated cites in tumour environment of Hcyanines together with incorporating morpholine in the molecule can enhance structure-inherent targeting of these dyes.

为了提高七次甲基花青 (Hcyanines) 在癌症研究中的效力，我们设计并合成了两种新型基于花青的治疗诊断探针IR794-Morph和IR794-Morph-Mpip ，以增强癌细胞的内化和靶向。在类似于肿瘤环境的酸性条件下，两种IR794衍生物均表现出宽的近红外吸收带（704-794 nm）和荧光发射（798-828 nm），适合深部肿瘤成像。此外，体外研究表明，与正常细胞相比，IR794-Morph-Mpip在生理和微酸性条件下对各种癌细胞系表现出更好的癌症靶向性。 IR794-Morph-Mpip在前 5 分钟内快速内化到癌细胞中，并且大部分定位于溶酶体和线粒体中。此外，当细胞处于缺氧环境时，内化信号更亮。此外，通过流式细胞术研究的两种IR794染料的细胞摄取机制表明，通过 OATP 受体的内吞作用和网格蛋白介导的内吞作用是主要途径。此外， IR794-Morph-Mpip对所有测试的癌细胞类型均显示出抗癌活性，IC ₅₀低于 7 μM（孵育 6 小时），大约比正常细胞低三倍。因此，增加花青素在肿瘤环境中的质子化引用以及在分子中掺入吗啉可以增强这些染料的结构固有靶向性。