Department of Biomaterials, College of Materials, ‡Fujian Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources, §State Key Laboratory of Physical Chemistry of Solid Surface, School of Chemistry and Chemical Engineering, and ∥Department of Electronic Science, College of Physical Science and Technology, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance Research, Xiamen University , Xiamen 361005, Fujian, P. R. China.
ACS Appl Mater Interfaces. 2017 Jun 7;9(22):19296-19306. doi: 10.1021/acsami.7b03087. Epub 2017 May 23.
This study reports a multifunctional nanoparticle (NP) that can be used for amplified magnetic resonance image (MRI)-guided photothermal therapy (PTT) due to its surface coating with a polydopamine (PDA) shell. Importantly, by means of introducing the surface coating of PDA, large quantities of water can be trapped around the NPs allowing more efficient water exchange, leading to greatly improved MR contrast signals compared with those from NPs without the PDA coating. Further, a distinct photothermal effect can be obtained arising from the strong absorption of PDA in the near-infrared (NIR) region. By synthesizing multifunctional MnCO@PDA NPs, for example, we found that the longitudinal relaxivity (r) of MnCO NPs can improve from 5.7 to 8.3 mM s. Subsequently, in vitro MRI and PTT results verified that MnCO@PDA could serve as an excellent MRI/PTT theranostic agent. Furthermore, the MnCO@PDA NPs were applied as an MRI/PTT theranostic agent for in vivo MRI-guided photothermal ablation of tumors by intratumoral injection in 4T1 tumor-bearing mice. The MR imaging result shows a significantly bright MR image in the tumor site. The MnCO@PDA-mediated PTT result shows high therapeutic efficiency as a result of high photothermal conversion efficiency. The present strategy of amplified MRI-guided PTT based on PDA coating of NPs will be widely applicable to other multifunctional NPs.
本研究报道了一种多功能纳米粒子（NP），由于其表面涂有聚多巴胺（PDA）壳，可用于放大磁共振成像（MRI）引导的光热治疗（PTT）。重要的是，通过引入 PDA 的表面涂层，可以在 NPs 周围捕获大量的水，从而允许更有效的水交换，与没有 PDA 涂层的 NPs 相比，产生的磁共振对比信号大大增强。此外，由于 PDA 在近红外（NIR）区域的强吸收，可获得明显的光热效应。例如，通过合成多功能 MnCO@PDA NPs，我们发现 MnCO NPs 的纵向弛豫率（r）可以从 5.7 提高到 8.3 mM s。随后，体外 MRI 和 PTT 结果验证了 MnCO@PDA 可以作为一种优秀的 MRI/PTT 治疗诊断试剂。此外，MnCO@PDA NPs 被用作 MRI/PTT 治疗诊断试剂，通过在 4T1 荷瘤小鼠瘤内注射进行体内 MRI 引导的肿瘤光热消融。磁共振成像结果显示肿瘤部位的磁共振图像明显明亮。由于高光热转换效率，MnCO@PDA 介导的 PTT 结果显示出高治疗效率。本研究基于 NPs 的 PDA 涂层的放大 MRI 引导 PTT 的策略将广泛适用于其他多功能 NPs。
