0000000000319552

AUTHOR

Hector Martinez-seara

0000-0001-9716-1713

showing 5 related works from this author

Cationic Au Nanoparticle Binding with Plasma Membrane-like Lipid Bilayers: Potential Mechanism for Spontaneous Permeation to Cells Revealed by Atomis…

2014

Despite being chemically inert as a bulk material, nanoscale gold can pose harmful side effects to living organisms. In particular, cationic Au nanoparticles (AuNP+) of 2 nm diameter or less permeate readily through plasma membranes and induce cell death. We report atomistic simulations of cationic Au nanoparticles interacting with realistic membranes and explicit solvent using a model system that comprises two cellular compartments, extracellular and cytosolic, divided by two asymmetric lipid bilayers. The membrane-AuNP+ binding and membrane reorganization processes are discovered to be governed by cooperative effects where AuNP+, counterions, water, and the two membrane leaflets all contr…

chemistry.chemical_classificationta114ta221Cationic polymerizationNanoparticlePermeationSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsGeneral EnergyMembranechemistryExtracellularBiophysicsOrganic chemistryPhysical and Theoretical ChemistryCounterionLipid bilayerta116Cellular compartment
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Atomistic Simulations of Functional Au_{144}(SR)_{60} Gold Nanoparticles in Aqueous Environment

2012

Charged monolayer-protected gold nanoparticles (AuNPs) have been studied in aqueous solution by performing atomistic molecular dynamics simulations at physiological temperature (310 K). Particular attention has been paid to electrostatic properties that modulate the formation of a complex comprised of the nanoparticle together with surrounding ions and water. We focus on Au-144 nanoparticles that comprise a nearly spherical Au core (diameter similar to 2 nm), a passivating Au-S interface, and functionalized alkanethiol chains. Cationic and anionic AuNPs have been modeled with amine and carboxyl terminal groups and Cl-/Na+ counterions, respectively. The radial distribution functions show tha…

chemistry.chemical_classificationAqueous solutionta114ChemistryCationic polymerizationNanoparticleNanotechnologySurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsMolecular dynamicsGeneral EnergySolvation shellChemical engineeringColloidal goldSide chainPhysical and Theoretical ChemistryCounterionThe Journal of Physical Chemistry C
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Atomistic Simulations of Functional Gold Nanoparticles Au144(Sr)60 Interacting with Membranes

2013

Gold nanoparticles (AuNps) are used in nanomedicine in, e.g., drug delivery and bio-imaging. However, it is regrettable that the understanding of nanoparticle properties in cellular surroundings is incompletely understood. Here, we have complemented our previous studies [1] by performing extensive atomistic molecular dynamics simulations of lipid membranes interacting with charged gold nanoparticles. We have elucidated the action of these nanoparticles on membranes characterized by lipid compositional asymmetry in the two leaflets, thereby unraveling the interactions of AuNPs with both the extracellular and the cytosolic sides of plasma membranes of eukaryotic cells. We have found that ther…

0303 health sciencesChemistryBiophysicsCationic polymerizationNanoparticleNanotechnology03 medical and health sciencesMolecular dynamics0302 clinical medicineMembraneColloidal goldDrug deliveryExtracellularNanomedicine030217 neurology & neurosurgery030304 developmental biology
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Topology and structure of Au144(SRNH3+)60 from "Atomistic Simulations of Functional Au144(SR)60 Gold Nanoparticles in Aqueous Environment"

2012

Positively charged monolayer-protected gold nanoparticles (AuNPs) structure and topology files for GROMACS used in DOI: 10.1021/jp301094m. The final structure of the simulation reported in DOI: 10.1021/jp301094m for the neutral case is provided. The gold nanoparticle contain a core of 144 Au atoms and 60 functionalized alkanethiol side groups (undecanyl chain, R = C11H22), each possessing a positively charged amonium terminal group. When using this structure do not forget to cite DOI: 10.1021/jp301094m. NOTE1: Different versions for the topology files are provided of both AuNPs. All versions were used for the publication. The changes only affect the core surface and therefore had no influ…

Molecular MechanicsSimulationUnited atom force fieldGold Nanoparticle
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Topology and structure of Au144(SRCOO-)60 from "Atomistic Simulations of Functional Au144(SR)60 Gold Nanoparticles in Aqueous Environment"

2012

Negatively charged monolayer-protected gold nanoparticles (AuNPs) structure and topology files for GROMACS used in DOI: 10.1021/jp301094m. The final structure of the simulation reported in DOI: 10.1021/jp301094m for the neutral case is provided. The gold nanoparticle contain a core of 144 Au atoms and 60 functionalized alkanethiol side groups (undecanyl chain, R = C11H22), each possessing a negatively charged carboxylic terminal group. When using this structure do not forget to cite DOI: 10.1021/jp301094m. NOTE1: Different versions for the topology files are provided of both AuNPs. All versions were used for the publication. The changes only affect the core surface and therefore had no in…

Molecular MechanicsSimulationUnited atom force fieldGold Nanoparticle
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