Untitled

Abstract

This review discusses the properties of complexes formed by proteins with polyelectrolytes (PPC) and two polyelectrolyte molecules of opposite charge (PEC). The most highly charged polymers with ionic groups in each monomer unit are considered in this paper. There are all reasons to regard PEC as macromolecular compounds produced as a result of equilibrium reactions with inherent permanent exchange of polyions in water-salt solutions. They combine two properties that might appear at first sight to be mutually exclusive, i.e. rather high stability and lability. Introduction of bioaffinity ligands endows PEC with the recognition capacity sufficient for the purposes of bioseparation and bioanalysis. Antibody-PEC conjugates were successfully used in the immunoassay combining the advantages of both homogeneous and heterogeneous assays and for modeling of chaperone action. The unique properties of polyelectrolyte complexes in combination with bioaffinity ligands makes them promising for the development of highly efficient means of protein isolation, new immunoassay procedures and creation of reversibly soluble biocatalysts.

Influence of Complexing Polyanions on the Thermostability of Basic Proteins

“…[9] Thus, when adding an equimolar amount of PEVP (monomer units of polycation per monomer units of polyanion), a complete restoration of the initial T max value for the protein was observed (curve 1 and curve 4 of Figure 1), indicating that all the protein molecules in solution became uncomplexed.…”

Interaction of lysozyme with negatively charged flexible chain polymers

“…Some authors [6,11,17] have postulated different theoretical models to describe the protein polyelectrolyte complex formation. However, these models are of difficult practical application to predict the behaviour of the system which makes it necessary to determine in a practical way the experimental variable values.…”

“…Complex formation by proteins with water-soluble synthetic polymers is interesting from two points of view [6]:…”

Chitosan‐based Polyelectrolyte Complexes Soluble in Enzyme‐friendly pH Range

“…Formation of soluble NPECs with relatively short lyophilizing chains is thermodynamically unfavorable, since this process is accompanied by losses in translational and configurational entropies, which are induced by immobilization of a large number of chains in the complex. [35] The shorter the polyanion, the greater the number of chains that should be immobilized in order to ensure the excess of negative charges required to lyophilize the complex, i.e., to transfer the insoluble complex to the soluble one, and the more pronounced the entropy losses will be, related to a reduction in the total amount of particles in solution. Accordingly, the region of existence of soluble NPECs narrows down (Z cr decreases), while, in the case of oligomeric anions, no soluble NPECs are formed ( Figure 8, region I).…”