Copper(II) diethyldithiocarbamate complex (CuET), the metabolite of disulfiram complexed with copper, is the component responsible for cancer treatment efficacy of disulfiram. But the hydrophobic property of CuET limits its use in vivo, and an appropriate drug delivery system needs to be developed. Ultrasmall melanin nanoparticle (M-Dot) with excellent biosafety and biocompatibility properties has been synthesized in our previous studies. Herein we prepared CuET loaded with M-Dots through hydrophobic interaction, which could enhance the water solubility significantly. After the administration of M-Dots-CuET in mice tumor models, the nanoparticles showed good tumor accumulation as evidenced by the enhanced photoacoustic signal in tumor regions. M-Dots-CuET also displayed excellent tumor inhibition capability, and the tumor growth inhibition value (TGI) was 45.1%. When combined with photothermal therapy, the TGI reached up to 78.6%. In summary, M-Dots-CuET provide a new potential strategy for cancer theranostics.

二乙基二硫代氨基甲酸铜 (II) 复合物 (CuET) 是双硫仑与铜络合的代谢物，是双硫仑治疗癌症疗效的主要成分。但是 CuET 的疏水性限制了它在体内的应用，并且需要开发合适的给药系统。我们之前的研究已经合成了具有优异生物安全性和生物相容性的超小黑色素纳米颗粒 (M-Dot)。在此，我们通过疏水相互作用制备了负载 M-Dots 的 CuET，这可以显着提高水溶性。在小鼠肿瘤模型中施用 M-Dots-CuET 后，纳米颗粒显示出良好的肿瘤积累，如肿瘤区域光声信号增强所证明。M-Dots-CuET也表现出优异的肿瘤抑制能力，肿瘤生长抑制值（TGI）为45.1%。结合光热疗法，TGI高达78.6%。总之，M-Dots-CuET 为癌症治疗诊断提供了一种新的潜在策略。