SCIENTIFIC HIGHLIGHTS

09 January 2018

Marcin P. Grzelczak*, Stephen P. Danks, Robert C. Klipp, Domagoj Belic, Adnana Zaulet, Casper Kunstmann-Olsen, Dan F. Bradley, Tatsuya Tsukuda, Clara Viñas, Francesc Teixidor, Jonathan J. Abramson, and Mathias Brust*. ACS Nano, Article ASAP. DOI: 10.1021/acsnano.7b06600

Carborane-capped gold nanoparticles (Au/carborane NPs, 2–3 nm) can act as artificial ion transporters across biological membranes. The particles themselves are large hydrophobic anions that have the ability to disperse in aqueous media and to partition over both sides of a phospholipid bilayer membrane. Their presence therefore causes a membrane potential that is determined by the relative concentrations of particles on each side of the membrane according to the Nernst equation. The particles tend to adsorb to both sides of the membrane and can flip across if changes in membrane potential require their repartitioning. Such changes can be made either with a potentiostat in an electrochemical cell or by competition with another partitioning ion, for example, potassium in the presence of its specific transporter valinomycin. Carborane-capped gold nanoparticles have a ligand shell full of voids, which stem from the packing of near spherical ligands on a near spherical metal core. These voids are normally filled with sodium or potassium ions, and the charge is overcompensated by excess electrons in the metal core. The anionic particles are therefore able to take up and release a certain payload of cations and to adjust their net charge accordingly. It is demonstrated by potential-dependent fluorescence spectroscopy that polarized phospholipid membranes of vesicles can be depolarized by ion transport mediated by the particles. It is also shown that the particles act as alkali-ion-specific transporters across free-standing membranes under potentiostatic control. Magnesium ions are not transported.

 

 

Hits: 3102
Bioactive materials for therapy and diagnosis

Ion Transport across Biological Membranes by Carborane-Capped Gold Nanoparticles



Also at ICMAB

  • Recombinant Human Epidermal Growth Factor/Quatsome Nanoconjugates: A Robust Topical Delivery System for Complex Wound Healing

    Information
    22 June 2021 48 hit(s) Biomaterials
    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.
  • In vivo soft tissue reinforcement with bacterial nanocellulose

    Information
    11 May 2021 293 hit(s) Biomaterials
    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 on Bacterial Nanocellulose Carriers for Ocular Surface Regeneration

    Information
    13 April 2021 405 hit(s) Biomaterials
    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.
  • Impact of Chemical Composition on the Nanostructure and Biological Activity of α-Galactosidase-Loaded Nanovesicles for Fabry Disease Treatment

    Information
    02 April 2021 436 hit(s) Biomaterials
    Fabry disease is a rare lysosomal storage disorder characterized by a deficiency of α-galactosidase A (GLA), a lysosomal hydrolase. The enzyme replacement therapy administering naked GLA shows several drawbacks including poor biodistribution, limited efficacy, and relatively high immunogenicity in Fabry patients.An attractive strategy to overcome these problems is the use of nanocarriers for encapsulating the enzyme. Nanoliposomes functionalized with RGD peptide have already emerged as a good platform to protect and deliver GLA to endothelial cells.
  • Radiolabeled Cobaltabis(dicarbollide) Anion–Graphene Oxide Nanocomposites for In Vivo Bioimaging and Boron Delivery

    Information
    23 March 2021 430 hit(s) Biomaterials
    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).

INSTITUT DE CIÈNCIA DE MATERIALS DE BARCELONA, Copyright © 2020 ICMAB-CSIC | Privacy Policy | This email address is being protected from spambots. You need JavaScript enabled to view it.