Fluorescent conjugated polyelectrolytes with pendant ionic sulfonate and carboxylate groups are used to sense protease activity. Inclusion of the fluorescent conjugated polyelectrolyte into the assay scheme leads to amplification of the sensory response. The sensing mechanism relies on an electrostatic interaction between the conjugated polyelectrolyte and a peptide substrate that is labeled wi...

electrostatic potential as well as the local volume charge density are computed for a macromolecule by solving the poisson-boltzmann equation (pbe) using the finite element method (fem). as a verification, our numerical results for a one dimensional pbe, which corresponds to an infinite-length macromolecule, are compared with the existing analytical solution and good agreement is found. as a ma...

Using extensive Molecular Dynamics simulations we study the behavior of polyelectrolytes with hydrophobic side chains, which are known to form cylindrical micelles in aqueous solution. We investigate the stability of such bundles with respect to hydrophobicity, the strength of the electrostatic interaction, and the bundle size. We show that for the parameter range relevant for sulfonated poly-p...

Monolayers of charged polystyrene latex particles ranging in size from 100 nm to 10 m were deposited on oppositely charged polyelectrolyte multilayers (PEMs) by electrostatic interactions and capillary forces. Ultrathin PEMs (∼30 nm) formed on a glass slide provided an e p i a l s c a ©

The adhesion and proliferation of bacteria on abiotic surfaces pose challenges related to human infection, including subsequent formation of antibiotic-resistant biofilms in both healthcare and industrial applications. Although the design of antibacterial materials is a longstanding effort, the surface properties that modulate adhesion of viable bacteria;the critical first step in biofilm forma...

It is well known that mechanical stimuli induce cellular responses ranging from morphological reorganization to mineral secretion, and that mechanical stimulation through modulation of the mechanical properties of cell substrata affects cell function in vitro and in vivo. However, there are few approaches by which the mechanical compliance of the substrata to which cells adhere and grow can be ...

A model of rod-like polyelectrolyte brushes in the presence of monovalent and multivalent counterions but with no added-salt is studied using Monte Carlo simulation. The average height of the brush, the histogram of rod conformations, and the counterion density profile are obtained for different values of the grafting density of the charge-neutral wall. For a domain of grafting densities, the b...

A new synthetic strategy has been developed for the fabrication of Au-Ag bimetallic core-shell nanoparticles (NPs) using polyelectrolyte multilayers (PEMs) as unique nanoreactors. Bimetallic NPs composed of Au core and Ag shell were successively incorporated into PEMs by repeating anion/cation exchange/reduction cycle multiple times in a stepwise manner. The strategy described here allows for t...

The problem of charged polymer chains (polyelectrolytes) as they adsorb on a planar surface is addressed theoretically. We review the basic mechanisms and theory underlying polyelectrolyte adsorption on a single surface in two situations: adsorption of a single charged chain, and adsorption from a bulk solution in θ solvent conditions. The behavior of flexible and semi-rigid chains is discussed...

2014 The adsorption of uncharged polymers is, due to numerous efforts over past decades, fairly well understood. Some insight exists into the structure of the adsorbed layer, and the effect of the important parameters molecular weight, solvency and polymer/surface interaction has been investigated. Theory and experiment are beginning to converge. The polyelectrolyte adsorption process, however,...