State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences , Beijing 100190, China.
University of Chinese Academy of Sciences , Beijing 100049, China.
J Am Chem Soc. 2017 Feb 8;139(5):1921-1927. doi: 10.1021/jacs.6b11382. Epub 2017 Jan 30.
Photothermal agents can harvest light energy and convert it into heat, offering a targeted and remote-controlled way to destroy carcinomatous cells and tissues. Inspired by the biological organization of polypeptides and porphyrins in living systems, here we have developed a supramolecular strategy to fabricate photothermal nanodots through peptide-modulated self-assembly of photoactive porphyrins. The self-assembling nature of porphyrins induces the formation of J-aggregates as substructures of the nanodots, and thus enables the fabrication of nanodots with totally inhibited fluorescence emission and singlet oxygen production, leading to a high light-to-heat conversion efficiency of the nanodots. The peptide moieties not only provide aqueous stability for the nanodots through hydrophilic interactions, but also provide a spatial barrier between porphyrin groups to inhibit the further growth of nanodots through the strong π-stacking interactions. Thermographic imaging reveals that the conversion of light to heat based on the nanodots is efficient in vitro and in vivo, enabling the nanodots to be applied for photothermal acoustic imaging and antitumor therapy. Antitumor therapy results show that these nanodots are highly biocompatible photothermal agents for tumor ablation, demonstrating the feasibility of using bioinspired nanostructures of self-assembling biomaterials for biomedical photoactive applications.
光热试剂可以吸收光能并将其转化为热能，提供一种靶向和遥控的方法来破坏癌性细胞和组织。受生物系统中多肽和卟啉的生物组织启发，我们开发了一种超分子策略，通过光活性卟啉的肽调节自组装来制备光热纳米点。卟啉的自组装性质诱导 J-聚集体作为纳米点的亚结构形成，从而能够制造完全抑制荧光发射和单线态氧产生的纳米点，导致纳米点具有高光热转换效率。肽部分不仅通过亲水相互作用为纳米点提供了水分散稳定性，而且通过强π-堆积相互作用在卟啉基团之间提供了空间障碍，以抑制纳米点的进一步生长。热成像显示，基于纳米点的光热转换在体外和体内都是有效的，使纳米点能够用于光热声成像和抗肿瘤治疗。抗肿瘤治疗结果表明，这些纳米点是高度生物相容的光热试剂，可用于肿瘤消融，证明了使用自组装生物材料的仿生纳米结构进行生物医学光活性应用的可行性。
