DataSheet1_Enhancing the Stability and Photothermal Conversion Efficiency of ICG by Pillar[5]arene-Based Host-Guest Interaction.doc

Indocyanine green (ICG) is a classical near-infrared (NIR) photothermal reagent that can be employed in clinical medical detection. Under neutral conditions, ICG can adsorb NIR light effectively for photothermal (PTT) and photodynamic (PDT) therapy. However, ICG is easily degraded in weak acid environments, which seriously restricts its application. In this work, a cationic water-soluble pillar[5]arene (WP5) was selected as the stabilizing agent for ICG. Thanks to the host-guest interaction between WP5 and alkyl sulfonate, the stability and the photothermal conversion efficiency of ICG increased remarkably upon addition of WP5 as investigated by UV-vis spectrum and photothermal studies. Furthermore, an in vitro study showed higher efficiency of WP5&ICG in killing cancer cells in a shorter treatment time than the free ICG. Hence, it is hopeful that WP5 can be a new type of supramolecular host in enhancing the stability and photothermal conversion efficiency of photosensitizers.

吲哚菁绿（Indocyanine green, ICG）是一类经典的近红外（NIR）光热试剂，可应用于临床医疗检测。在中性条件下，ICG可有效吸附近红外光，用于光热（PTT）与光动力（PDT）治疗。然而，ICG在弱酸性环境中极易发生降解，严重制约了其应用范围。本研究遴选阳离子水溶性柱[5]芳烃（WP5）作为ICG的稳定剂。经紫外-可见光谱与光热性能表征发现，依托WP5与烷基磺酸盐之间的主客体相互作用，添加WP5后可显著提升ICG的稳定性与光热转换效率。进一步的体外实验结果表明，相较于游离ICG，WP5与ICG的复合体系可在更短的处理时长内实现更高效率的癌细胞杀伤。因此，WP5有望成为一类新型超分子主体，用于增强光敏剂的稳定性与光热转换效率。