Photothermal therapies (PPTs) with various light-absorbing materials have shown very promising therapeutic effects against cancers. However, their application was severely limited by the lack of accurate localization of tumors and real-time monitoring of the therapeutic process. Theranostic nanoparticles with both imaging and therapeutic functions are highly desired to develop imaging-mediated PPTs. Herein, we develop a facile one-pot method to synthesize a nanoparticle with functions of an MRI contrast agent and a PTT agent through oxidization of dopamine-DTPA-Gd conjugates and PEG-dopamine conjugates. The oxidized dopamine nanoparticles (ODNP) had a high R1 up to 9.6 mM⁻¹ s⁻¹, 2.2 times higher than that of Omniscan, and showed significantly higher MRI contrast enhancement than Omniscan in tumor. Meanwhile, the ODNP showed strong NIR light absorption and significant antitumor efficacy both in vitro and in vivo as a PPT agent. The ODNP with excellent MRI contrasting capability and PTT efficacy plus its facile synthesis and good biocompatibility are a very promising theranostic agent for MRI-mediated PTT.

中文翻译：

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通过多巴胺-DTPA-Gd共轭物的氧化轻松合成治疗型纳米颗粒

具有多种吸光材料的光热疗法（PPT）已显示出非常有前途的抗癌治疗作用。然而，由于缺乏对肿瘤的精确定位和对治疗过程的实时监控，它们的应用受到了严重限制。具有成像和治疗功能的治疗性纳米颗粒非常需要开发成像介导的PPT。本文中，我们开发了一种简便的一锅法，通过多巴胺-DTPA-Gd缀合物和PEG-多巴胺缀合物的氧化来合成具有MRI造影剂和PTT剂功能的纳米颗粒。氧化多巴胺纳米颗粒（ODNP）的R1高达9.6 mM ^-1 s ^-1，是Omniscan的2.2倍，并且在肿瘤中显示出比Omniscan显着更高的MRI对比度增强。同时，ODNP作为PPT剂在体外和体内均显示出强的NIR光吸收和显着的抗肿瘤功效。具有出色的MRI对比能力和PTT功效的ODNP以及其简便的合成和良好的生物相容性是用于MRI介导的PTT的非常有前途的治疗剂。