Institutes for Life Sciences, School of Medicine and National Engineering Research Center for Tissue Restoration and Reconstruction, South China University of Technology, Guangzhou, Guandong 510006, P.R. China.
Academy of Opto-Electronic Technology, Hefei University of Technology, Hefei, Anhui 230009, P.R. China.
Theranostics. 2017 Sep 20;7(16):4029-4040. doi: 10.7150/thno.19538. eCollection 2017.
The donor-acceptor semiconducting polymers (SPs) have robust absorbance in near-infrared (NIR) region, great photostability, high photothermal conversion efficiency, and good biocompatibility. Thus, the SPs exhibit great potentials for photothermal therapy (PTT) and photoacoustic imaging (PAI). However, poor understanding of the underlying mechanisms and the correlation between the SP polymer chemical structures and their performances of PTT and PAI have significantly hindered their biomedical application. Herein, a series of acceptor-π-acceptor type (A1-π-A2) type SPs were synthesized. The diketopyrrolopyrrole (DPP) and thiophene are used as A1 electron accepting block and π-bridge, and the chemical structure of A2 unit was variable. The SPs were formulated into PEGylated nanoparticles, which ensured these SP-based nanoparticles (SP@NPs) exhibited similar size, shape, and physiological stability. Thus, the chemical structure of A2 unit was the only variable. The effects of the SP chemical structures are carefully and comprehensively evaluated through both and experiments. Our results demonstrated the chemical structure of A2 unit simultaneously impact their absorption spectra and photothermal (PT) conversion efficiency, which finally determined their PTT and PAI performances. Among these A2 acceptors, thieno[3,2-b]thiophene (TT) unit exhibited the best and anticancer efficacies and PAI performances. This study not only provides molecular insights into the design of efficient SPs for PTT and PAI but also highlights the flexibility and potential of SP@NPs for biomedical application. Thus, SP@NPs can act as a versatile nanoplatform for the development of novel light intensive imaging and therapeutic approaches.
供体-受体半导体聚合物（SPs）在近红外（NIR）区域具有较强的吸光度、良好的光稳定性、高光热转换效率和良好的生物相容性。因此，SPs 在光热治疗（PTT）和光声成像（PAI）方面具有很大的应用潜力。然而，对其内在机制以及 SP 聚合物化学结构与其 PTT 和 PAI 性能之间的相关性缺乏深入了解，这极大地阻碍了它们在生物医学中的应用。在此，我们合成了一系列受体-π-受体型（A1-π-A2）SP。二酮吡咯并吡咯（DPP）和噻吩分别作为 A1 电子受体和π桥，A2 单元的化学结构是可变的。将 SP 制成聚乙二醇化纳米粒子，确保这些基于 SP 的纳米粒子（SP@NPs）具有相似的尺寸、形状和生理稳定性。因此，A2 单元的化学结构是唯一的变量。通过 和 实验，我们仔细而全面地评估了 SP 化学结构的影响。我们的结果表明，A2 单元的化学结构同时影响它们的吸收光谱和光热（PT）转换效率，最终决定了它们的 PTT 和 PAI 性能。在这些 A2 受体中，噻吩[3,2-b]噻吩（TT）单元表现出最好的 和 抗癌疗效和 PAI 性能。本研究不仅为设计用于 PTT 和 PAI 的高效 SP 提供了分子见解，还突出了 SP@NPs 在生物医学应用中的灵活性和潜力。因此，SP@NPs 可以作为一种通用的纳米平台，用于开发新型的强光照成像和治疗方法。
