Polydopamine Coated Single-Walled Carbon Nanotubes as a Versatile Platform with Radionuclide Labeling for Multimodal Tumor Imaging and Therapy

Abstract

Single-walled carbon nanotubes (SWNTs) with various unique properties have attracted great attention in cancer theranostics. Herein, SWNTs are coated with a shell of polydopamine (PDA), which is further modified by polyethylene glycol (PEG). The PDA shell in the obtained SWNT@PDA-PEG could chelate Mn2+, which together with metallic nanoparticulate impurities anchored on SWNTs offer enhanced both T1 and T2 contrasts under magnetic resonance (MR) imaging. Meanwhile, also utilizing the PDA shell, radionuclide 131I could be easily labeled onto SWNT@PDA-PEG, enabling nuclear imaging and radioisotope cancer therapy. As revealed by MR & gamma imaging, efficient tumor accumulation of SWNT@PDA-131I-PEG is observed after systemic administration into mice. By further utilizing the strong near-infarared (NIR) absorbance of SWNTs, NIR-triggered photothermal therapy in combination with 131I-based radioisotope therapy is realized in our animal experiments, in which a remarkable synergistic antitumor therapeutic effect is observed compared to monotherapies. Our work not only presents a new type of theranostic nanoplatform based on SWNTs, but also suggests the promise of PDA coating as a general approach to modify nano-agents and endow them with highly integrated functionalities.

Carbon Nanotubes as an Effective Opportunity for Cancer Diagnosis and Treatment

“…As revealed by MR and gamma imaging, efficient tumor accumulation of SWNT@PDA-${}^1$31I-PEG was observed by the authors after systemic administration into mice. Moreover, they exploited the strong NIR absorbance of SWNTs, to perform NIR-triggered photothermal therapy in combination with ${}^1$31I-based radioisotope therapy to destroy the cancer with good results [101]. Such emerging multimodal contrast agents will be a valuable tool for tumor imaging, as well as theranostic and guidance applications in radiation therapy [102].…”

Nanotechnologies for early diagnosis, in situ disease monitoring, and prevention

“…Remarkably, blank liposomes presented similar protection results as compared to those carrying −2 RANTES. 96 A possible explanation may be the inherent antiviral activity of Novasome 7474 as documented for other liposomal vesicles. 98,99 In any case, the ability of liposomes to evenly distribute throughout the mucosa seems to have been important for creating a protective barrier against viral transmission.…”

“…The efficacy of these complexes against vaginal transmission of CCR5-tropic SHIV 162P3 was further tested in cynomolgus macaques. 96 Pretreatment (30-45 min) of animals with −2 RANTES/liposome complexes in PBS before viral challenge resulted in partial yet significant protection as compared to animals treated with PBS alone. −2 RANTES in PBS solution provided no significant protection when used at a concentration up to nearly 4 times of that used for complexes.…”

“…One exception has been the use of commercially available Novasome 7474 (Novavax, Gaithersburg, Maryland, USA and IGI Laboratories, Buena, New Jersey, USA) for the vaginal delivery of −2 RANTES, a truncated fragment of Regulated on Activation, Normal T Expressed and Secreted (RANTES) chemokine presenting high specificity for CCR5 binding. 95,96 Novasome are 200-700 nm nonphospholipidic liposomes comprising monoesters of PEO fatty acids, cholesterol, and free fatty acids. 97 The association of −2 RANTES with Novasome did not affect the native activity of the protein.…”

“…97 The association of −2 RANTES with Novasome did not affect the native activity of the protein. 95,96 Data from an initial study by Kish-Catalone et al 95 were able to indicate that −2 RANTES/ liposome complexes elicited only mild signs of inflammation when administered to mice (single dose) and rabbits (daily administration for 10 consecutive days), thus being considered acceptable for vaginal use. The efficacy of these complexes against vaginal transmission of CCR5-tropic SHIV 162P3 was further tested in cynomolgus macaques.…”