In this chapter, we review our recent theoretical work on the formation of polyelectrolyte multilayers. The first layer is obtained by polyelectrolyte adsorption on a surface with an opposite charge. The adsorbed polyelectrolyte charge is sufficient to invert the charge of the surface. Each subsequent layer is bound to the previous one by the formation of a polyelectrolyte complex. Using a Deby...

Self-assembly processes of polyelectrolyte block copolymers are ubiquitous in industrial and biological processes; understanding their physical properties can also provide insights into the design of polyelectrolyte materials with novel and tailored properties. Here, we report systematic analysis on how the ionic strength of the solvent and the length of the polyelectrolyte block affect the sel...

We present the results of Monte Carlo simulations of complexation between polyampholyte and polyelectrolyte chains. Polymers are modeled as bead-spring chains of charged Lennard-Jones particles each consisting of 32 monomers. Formation of a polyampholyte-polyelectrolyte complex is driven by polarization-induced attractive interactions. The complex is usually formed at the end of the polyelectro...

We review recent experiments on the interaction of proteins with anionic polyelectrolytes in aqueous solution. Data from the literature demonstrate that proteins can form soluble complexes with linear polyelectrolytes even on the "wrong side" of the isoelectric point, that is, for pH values above the isoelectric point of the proteins under which the polyelectrolytes and the proteins are like-ch...

Polyelectrolyte adsorption can be used to modify the surface of chromatographic packings in order to make them more suitable for protein separations. We studied the binding of proteins to controlled pore glass (CPG) on which the polycation poly(diallyldimethylammonium chloride) (PDADMAC) was noncovalently immobilized through electrostatic interaction. We found that the selectivity of PDADMAC fo...

the effect of epinephrine on triacylglycerol secretion was investigated in isolated rat hepatocytes. the effect appeared at concentrations of more than 1 µm and reached a plateau at 10 µm. epinephrine concentration for half of the maximal bioeffect (ec50) was about 1 µm. epineplrrine at a concentration of 10 µm suppressed triacylglycerol secretion by 33% and increased its cellular content by ap...

Most of the modern theories of grafted polyelectrolyte brushes are valid only for moderate stretching of the polyelectrolyte. However, particularly at low ionic strength and high grafting densities, even a moderate charge of the polyelectrolyte can generate a strong stretching. A simple mean field model for strongly stretched grafted polyelectrolyte brushes is suggested, based on an approximate...

Complex formation between a weak flexible polyelectrolyte chain and one positively charged nanoparticle in presence of explicit counterions and salt particles is investigated using Monte Carlo simulations. The influence of parameters such as the nanoparticle surface charge density, salt valency, and solution property such as the pH on the chain protonation/deprotonation process and monomer adso...

The possible backbone phosphodiester conformations in a dinucleoside monophosphate and a dinucleoside triphosphate have been investigated by semiempirical energy calculations. Conformational energies have been computed as a function of the rotations omega' and omega about the internucleotide P-O(3') and P-O(5') linkages, with the nucleotide residues themselves assumed to be in one of the prefer...

Polynucleotide kinase from E. coli infected with the PseT 1 mutant of bacteriophage T4 has been isolated. The PseT 1 enzyme purifies similarly to normal polynucleotide kinase and effectively transfers the gamma phosphate of ATP to the 5' terminal hydroxyl of DNA and RNA. The PseT 1 and normal enzymes require similar magnesium ion concentrations, have the same pH optima and are both inhibited by...