Synthesis of strong electron donating-accepting type organic fluorophore and its polypeptide nanoparticles for NIR-II phototheranostics

• Published in: Nanomedicine 2022-08, Vol.44, p.102574-102574, Article 102574
• Main Authors: Teng, Changchang, Zhang, Shangzhong, Tian, Youliang, Cheng, Quan, Dang, Huiping, Yin, Dalong, Yan, Lifeng
• Format: Article
• Language: English
• Subjects: Anticancer; Nanotheranostic; NIR-II fluorescence imaging; Photothermal therapy
• ISSN: 1549-9634; 1549-9642
• DOI: 10.1016/j.nano.2022.102574

A novel NIR-II small-molecule D-A type organic fluorophore conjugation of triphenylamine, thiophene, and benzo[c,d] indol groups (TPA-Et) with strong electron-donating and accepting groups has been synthesized. The dye shows a significant Stokes shift for efficient fluorescence in the NIR-II region and high photothermal performance. The TPA-Et was then encapsulated by an amphiphilic copolymer P(OEGMA)20-P(Asp)14, and micelles (P@TP) has been prepared with outstanding NIR-II imaging performance, excellent photothermal conversion efficiency (52.5%) under 808 nm laser irradiation, and good photostability. Fluorescence imaging experiments have consistently shown that P@TP can image tiny blood vessels in mice, enrich effectively in the tumor region, and maintain a relatively stable NIR-II fluorescence signal in the tumor area for a long time up to 60 h. In vivo photothermal therapy has a highly significant anticancer effect without tumor recurrence, demonstrating the apparent advantages of P@TP as a NIR nanotheranostic platform in NIR-II imaging-guided photothermal therapy. A NIR-II probe with D-A structure and large Stokes shift has been prepared, which has outstanding photothermal performance (PCE = 52.5%) and a long time window of up to 60 h for NIR-II tumor imaging-guided treatment. The nanoparticles demonstrate superior anti-tumor ability, without any recurrence after therapy. [Display omitted]