A carbon-based hybrid nanocomposite, which consists of monoiodinated boron-cluster derivatives covalently attached to graphene oxide, is hereby introduced. This GO-I-COSAN has been synthesized using a novel boron-rich cobaltabis(dicarbollide) precursor with one iodide group attached to one of the boron atoms of the cluster (I-COSAN) and designed to be subsequently labeled with radioactive 124I for its use in positron emission tomography (PET).
In vitro cytotoxicity studies of GO-I-COSAN with HeLa cells at different concentrations up to 48 h proved that the cell mortality was lower than 10%, indicating minimal cytotoxicity of the nanomaterial. Remarkably, internalization of the nanomaterial by cells was confirmed by transmission electron microscopy, which indicated its accumulation in the cytoplasm, without causing changes in either the size or morphology of the cells. Additionally, in vivo tests using Caenorhabditis elegans confirmed that GO-I-COSAN could be ingested by the worms, showing no significant damage and very low toxicity, which supports the results observed in the in vitro studies. Radioisotopic labeling of I-COSAN using a palladium-catalyzed isotopic exchange reaction with Na[124I]I and its subsequent functionalization onto GO was performed successfully, leading to formation of the radioactive nanocomposite GO-[124I]I-COSAN, which was quickly injected in mice. PET images at different times revealed excellent in vivo stability of the developed nanomaterial. No activity in thyroid and stomach was observed even at long times, proving that iodide did not detach from the material. GO-[124I]I-COSAN presented a favorable biodistribution profile, being mainly accumulated in the liver and slightly in the lung, with a long residence time on blood and progressive elimination via the gastrointestinal tract. It is noteworthy that the high boron content of this material paves the way toward theranostics because it benefits of a traceable boron delivery for boron neutron capture therapy.
Bioactive materials for therapy and diagnosis
Radiolabeled Cobaltabis(dicarbollide) Anion–Graphene Oxide Nanocomposites for In Vivo Bioimaging and Boron Delivery
Albert Ferrer-Ugalde, Stefania Sandoval, Krishna Reddy Pulagam, Amanda Muñoz-Juan, Anna Laromaine, Jordi Llop, Gerard Tobias*, and Rosario Núñez*
Carbon dots are an emerging family of zero-dimensional nanocarbons behaving as tunable light harvesters and photoactivated charge donors. Coupling them to carbon nanotubes, which are well-known electron acceptors with excellent charge transport capabilities, is very promising for several applications.
Fabricating polymeric scaffolds using cost-effective manufacturing processes is still challenging. Gas foaming techniques using supercritical carbon dioxide (scCO2) have attracted attention for producing synthetic polymer matrices; however, the high-pressure requirements are often a technological barrier for its widespread use. Compressed 1,1,1,2-tetrafluoroethane, known as Freon R134a, offers advantages over CO2 in manufacturing processes in terms of lower pressure and temperature conditions and the use of low-cost equipment.
The increasing use of mechanical thrombectomy in stroke management has opened the window to local intraarterial brain delivery of therapeutic agents. In this context, the use of nanomedicine could further improve the delivery of new treatments for specific brain targeting, tracking and guidance. In this study we take advantage of this new endovascular approach to deliver biocompatible poly(D-L-lactic-co-glycolic acid) (PLGA) nanocapsules functionalized with superparamagnetic iron oxide nanoparticles and Cy7.5 for magnetic targeting, magnetic resonance and fluorescent molecular imaging.
The anionic cobaltabis (dicarbollide) [3,3′-Co(1,2-C2B9H11)2]−, [o-COSAN]−, is the most studied icosahedral metallacarborane. The sodium salts of [o-COSAN]− could be an ideal candidate for the anti-cancer treatment Boron Neutron Capture Therapy (BNCT) as it possesses the ability to readily cross biological membranes thereby producing cell cycle arrest in cancer cells. BNCT is a cancer therapy based on the potential of 10B atoms to produce α particles that cross tissues in which the 10B is accumulated without damaging the surrounding healthy tissues, after being irradiated with low energy thermal neutrons.
The development of artificial vesicles into responsive architectures capable of sensing the biological environment and simultaneously signaling the presence of a specific target molecule is a key challenge in a range of biomedical applications from drug delivery to diagnostic tools. Herein, the rational design of biomimetic DNA-grafted quatsome (QS) nanovesicles capable of translating the binding of a target molecule to amphiphilic DNA probes into an optical output is presented.