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*
This paper describes the transition from the normal to inverted Marcus region in solid-state tunnel junctions consisting of self-assembled monolayers of benzotetrathiafulvalene (BTTF), and how this transition determines the performance of a molecular diode. Temperature-dependent normalized differential conductance analyses indicate the participation of the HOMO (highest occupied molecular orbital) at large negative bias, which follows typical thermally activated hopping behavior associated with the normal Marcus regime.
Four novel transition metal-carborane photosensitisers were prepared by Sonogashira cross-coupling of 1-(4-ethynylbenzyl)-2-methyl-o-carborane (A-CB) with halogenated Ru(II)- or Ir(III)-phenanthroline complexes. The resulting boron-rich complexes with one (RuCB and IrCB) or two carborane cages (RuCB2 and IrCB2) were spectroscopically characterised, and their photophysical properties investigated. RuCB displayed the most attractive photophysical properties in solution (λem 635 nm, τT 2.53 μs, and φp 20.4 %).
A multitude of microparticles and nanoparticles is developed to improve the delivery of different small drugs and large biomolecules, which are subject to several hindering biological barriers that limit their optimal biodistribution and therapeutic effects. Here, a soft, reliable, and scalable method based on compressed CO2 is reported for obtaining nanoconjugates of recombinant human epidermal growth factor and nanovesicles called quatsomes, where the latter consists of cholesterol and cetyltrimethylammonium bromide.These nanoconjugates exhibit appropriate values of the major critical quality attributes of colloidal nanomedicines, such as controlled and narrow nanoscopic particle size distribution (which play important roles in determining their stability), drug loading, drug release, drug protection, targeting ability, and bioactivity.
The use of surgical meshes to reinforce damaged internal soft tissues has been instrumental for successful hernia surgery; a highly prevalent condition affecting yearly more than 20 million patients worldwide. Intraperitoneal adhesions between meshes and viscera are one of the most threatening complications, often implying reoperation or side effects such as chronic pain and bowel perforation.
Limbal stem cells (LSCs) are already used in cell‐based treatments for ocular surface disorders. Clinical translation of LSCs‐based therapies critically depends on the successful delivery, survival, and retention of these therapeutic cells to the desired region. Such a major bottleneck could be overcome by using an appropriate carrier to provide anchoring sites and structural support to LSC culture and transplantation.