Spadix-Bract Structured Nanobowls for Bimodal Imaging-Guided\nMultidrug Chemo-Photothermal Synergistic Therapy

Abstract

Multifunctional\nnanoparticles (NPs) simultaneously having functions\nof multimodal therapy and imaging are highly needed in biomedical\napplications. A unique monstera flower-like gold nanorod/polydopamine\nbowl (GNR/PDA bowl) with spadix-bract nanostructure was fabricated\nby a novel and facile approach. The possible formation mechanism of\nthe GNR/PDA bowl spadix-bract NPs was proposed by monitoring the synthetic\nprocess. The obtained monstera flower-like GNR/PDA bowl spadix-bract\nNPs were further selectively functionalized with 1-dodecanethiol (DT)\non GNR domains (spadix) to achieve efficient hydrophobic drug delivery\ncapability; meanwhile, the PDA bowl (bract) can load the hydrophilic\nanticancer drug doxorubicin (DOX). The resultant monstera flower-like\nDT-GNR/PDA bowl spadix-bract NPs possess an excellent biocompatibility,\nhigh dual-drug-loading contents, excellent photothermal conversion\nefficiency, strong near-infrared (NIR) absorbance, effective attenuation\nof X-rays, and pH/NIR dual-responsive properties, which enable the\nNPs to be applied for synergistic bimodal computed tomography/photoacoustic\n(CT/PA) imaging-guided multidrug chemotherapy and photothermal therapy\n(PTT). Moreover, the synthetic approach could be extended to prepare\nAu/PDA bowl NPs and Fe₂O₃/PDA bowl NPs, which\nmay greatly expand the application of the PDA-based bowl NPs.