Conjugated Polymer for NIR-II Phototheranostics toward Tumor

Due to the strong light trapping ability, good biocompatibility, and easily regulated molecular structure, conjugated polymers are becoming a promising tool for phototheranostics of tumors, which can achieve both precise diagnosis and efficient therapeutics. Of particular interest is conjugated polymer-based theranostic agents applying to the second near-infrared (NIR-II) window (1000–1700 nm), which exhibit great potential for clinical applications on account of the extremely long wavelength. Herein, the basic mechanism, advances in recent 6 years, and perspectives of conjugated polymer for NIR-II phototheranostics toward tumor are discussed successively. First, the basic mechanisms of the most widely employed modalities for conjugated polymer-based NIR-II phototheranostics are presented. In view of the heat generation property of conjugated polymer under photoexcitation, the most widely employed modalities for conjugated polymer-based NIR-II phototheranostics are fluorescence imaging (FLI)-guided photothermal therapy (PTT) and photoacoustic imaging (PAI)-guided PTT. Then, the recent related advances of NIR-II FLI-guided NIR-II PTT technology, NIR-II PAI-guided NIR-II PTT technology, and multimodel theranostics are introduced. Finally, the perspectives for the development of conjugated polymer-based NIR-II phototheranostics is illustrated for the practical application of simultaneously diagnosis and in situ therapy for tumor.