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Title: Bilayers in nanoparticle-doped polar mesogens

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  1. (Paderborn)
  2. (
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
Sponsoring Org.:
OSTI Identifier:
Resource Type:
Journal Article
Resource Relation:
Journal Name: Phys. Rev. E; Journal Volume: 88; Journal Issue: (6) ; 12, 2013
Country of Publication:
United States

Citation Formats

Lorenz, Alexander, Agra-Kooijman, Deña M., Zimmermann, Natalie, Kitzerow, Heinz-S., Evans, Dean R., Kumar, Satyendra, Cambridge), Kent), and AFRL). Bilayers in nanoparticle-doped polar mesogens. United States: N. p., 2014. Web. doi:10.1103/PhysRevE.88.062505.
Lorenz, Alexander, Agra-Kooijman, Deña M., Zimmermann, Natalie, Kitzerow, Heinz-S., Evans, Dean R., Kumar, Satyendra, Cambridge), Kent), & AFRL). Bilayers in nanoparticle-doped polar mesogens. United States. doi:10.1103/PhysRevE.88.062505.
Lorenz, Alexander, Agra-Kooijman, Deña M., Zimmermann, Natalie, Kitzerow, Heinz-S., Evans, Dean R., Kumar, Satyendra, Cambridge), Kent), and AFRL). 2014. "Bilayers in nanoparticle-doped polar mesogens". United States. doi:10.1103/PhysRevE.88.062505.
title = {Bilayers in nanoparticle-doped polar mesogens},
author = {Lorenz, Alexander and Agra-Kooijman, Deña M. and Zimmermann, Natalie and Kitzerow, Heinz-S. and Evans, Dean R. and Kumar, Satyendra and Cambridge) and Kent) and AFRL)},
abstractNote = {},
doi = {10.1103/PhysRevE.88.062505},
journal = {Phys. Rev. E},
number = (6) ; 12, 2013,
volume = 88,
place = {United States},
year = 2014,
month = 2
  • Abstract not provided.
  • Many nanocarrier cancer therapeutics currently under development, as well as those used in the clinical setting, rely upon the enhanced permeability and retention (EPR) effect to passively accumulate in the tumor microenvironment and kill cancer cells. In leukemia, where leukemogenic stem cells and their progeny circulate within the peripheral blood or bone marrow, the EPR effect may not be operative. Thus, for leukemia therapeutics, it is essential to target and bind individual circulating cells. Here in this research, we investigate mesoporous silica nanoparticle (MSN)-supported lipid bilayers (protocells), an emerging class of nanocarriers, and establish the synthesis conditions and lipid bilayermore » composition needed to achieve highly monodisperse protocells that remain stable in complex media as assessed in vitro by dynamic light scattering and cryo-electron microscopy and ex ovo by direct imaging within a chick chorioallantoic membrane (CAM) model. We show that for vesicle fusion conditions where the lipid surface area exceeds the external surface area of the MSN and the ionic strength exceeds 20 mM, we form monosized protocells (polydispersity index <0.1) on MSN cores with varying size, shape, and pore size, whose conformal zwitterionic supported lipid bilayer confers excellent stability as judged by circulation in the CAM and minimal opsonization in vivo in a mouse model. Having established protocell formulations that are stable colloids, we further modified them with anti-EGFR antibodies as targeting agents and reverified their monodispersity and stability. Then, using intravital imaging in the CAM, we directly observed in real time the progression of selective targeting of individual leukemia cells (using the established REH leukemia cell line transduced with EGFR) and delivery of a model cargo. In conclusion, overall we have established the effectiveness of the protocell platform for individual cell targeting and delivery needed for leukemia and other disseminated disease.« less
  • Low-energy two-dimensional scattering is particularly sensitive to the existence and the properties of weakly bound states. We show that interaction potentials V(r) with the vanishing zero-momentum Born approximation {integral}dr rV(r)=0 leads to an anomalously weak bound state that crucially modifies the two-dimensional scattering properties. This anomalous case is especially relevant in the context of polar molecules in bilayer arrangements.
  • The observation of significant dipolar effects in gases of ultracold polar molecules typically demands a strong external electric field to polarize the molecules. We show that, even in the absence of a significant polarization, dipolar effects may play a crucial role in the physics of polar molecules in bilayers, provided that the molecules in each layer are initially prepared in a different rotational state. Then, interlayer dipolar interactions result in a nonlocal swap of the rotational state between molecules in different layers, even for weak applied electric fields. The interlayer scattering due to the dipole-dipole interaction leads to a nontrivialmore » dependence of the swapping rate on density, temperature, interlayer spacing, and population imbalance. For reactive molecules such as KRb, chemical recombination immediately follows a nonlocal swap and dominates the losses even for temperatures well above quantum degeneracy, and hence could be observed under current experimental conditions.« less
  • The electronic properties of Mott insulators realized in (111) bilayers of perovskite transition-metal oxides are studied. The low-energy effective Hamiltonians for such Mott insulators are derived in the presence of a strong spin-orbit coupling. These models are characterized by the antiferromagnetic Heisenberg interaction and the anisotropic interaction whose form depends on themore » $d$ orbital occupancy. From exact diagonalization analyses on finite clusters, the ground state phase diagrams are derived, including a Kitaev spin liquid phase in a narrow parameter regime for $$t_{2g}$$ systems. Slave-boson mean-field analyses indicate the possibility of novel superconducting states induced by carrier doping into the Mott-insulating parent systems, suggesting the present model systems as unique playgrounds for studying correlation-induced novel phenomena. Possible experimental realizations are also discussed.« less