Recently developed DNA-based analogues of membrane proteins have advanced synthetic biology. A fundamental question is how hydrophilic nanostructures reside in the hydrophobic environment of the membrane. Here, we use multiscale molecular dynamics (MD) simulations to explore the structure, stability and dynamics of an archetypical DNA nanotube inserted via a ring of membrane anchors into a phos...

Using molecular dynamics simulations in combination with scaling analysis, we have studied the effects of the solvent quality and the strength of the electrostatic interactions on the conformations of spherical polyelectrolyte brushes in salt-free solutions. The spherical polyelectrolyte brush could be in one of four conformations: (1) a star-like conformation, (2) a "star of bundles" conformat...

Layer-by-layer self-assembled polyelectrolyte shells are a new class of micro/nanocapsules with unique physicochemical properties for potential applications in drug/gene delivery. The objective of this study was to investigate the interactions of polyelectrolyte shells ( approximately 1 mum in diameter) with MCF-7 breast cancer cells and identify key parameters that affect such interactions. Ta...

Based on extensive Monte Carlo simulations and analytical considerations we study the electrostatically driven adsorption of flexible polyelectrolyte chains onto charged Janus nanospheres. These net-neutral colloids are composed of two equally but oppositely charged hemispheres. The critical binding conditions for polyelectrolyte chains are analysed as function of the radius of the Janus partic...

FK-506 binding protein (FKBP12) is a protein of the family of immunophilins, involved in many neurodegenerative diseases such as Alzheimer’s syndrome where FKBP12 is known to be over-expressed in early stages of the disease. We designed and built Langmuir-Blodgett nanostructures incorporating ligands with high affinity for FKBP12: Tacrolimus (FK506) and Rifaximin as candidate nanosensors to det...

A universal description is presented for weak adsorption of flexible polyelectrolyte chains onto oppositely charged planar and curved surfaces. It is based on the WKB (Wentzel-Kramers-Brillouin) quantum mechanical method for the Green function equation in the ground state dominance limit. The approach provides a unified picture for the scaling behavior of the critical characteristics of polyele...

We develop a scaling model relating the friction forces between two polyelectrolyte brushes sliding over each other to the separation between grafted surfaces, number of monomers and charges per chain, grafting density of chains, and solvent quality. We demonstrate that the lateral force between brushes increases upon compression, but to a lesser extent than the normal force. The shear stress a...