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Conjugation of Polymers with Biomolecules and Polymeric Vaccine Development Technologies
Published in Mesut Karahan, Synthetic Peptide Vaccine Models, 2021
The importance of polyelectrolyte use in immunology: Analysis of functional properties of complexes that dissolve in water which is made with synthetic polyelectrolytes (PE) and biomacromolecules (protein, peptide, polysaccharide, etc.) is a remarkable immunological development.These types of synthetic polymers are used in important practice areas of medicine and biological-based sciences.
Design of Bioresponsive Polymers
Published in Deepa H. Patel, Bioresponsive Polymers, 2020
Anita Patel, Jayvadan K. Patel, Deepa H. Patel
The presence of ionizable, weakly acidic or basic moieties, are the vital constituent for pH-responsive polymers that connect to a hydrophobic backbone, like polyelectrolytes [48, 128, 129]. The electrostatic repulsions of the produced anions or cations charges bring about a theatrical addition of coiled chains after ionization. As a result of the electrostatic effect as of other adjacent ionized groups, the ionization of the pendant acidic (e.g., carboxylic, and sulfonic acids) or basic (e.g., ammonium salts) groups on polyelectrolytes can be fractional [129, 130].
Injectable Scaffolds for Bone Tissue Repair and Augmentation
Published in Naznin Sultana, Sanchita Bandyopadhyay-Ghosh, Chin Fhong Soon, Tissue Engineering Strategies for Organ Regeneration, 2020
Subrata Bandhu Ghosh, Kapender Phogat, Sanchita Bandyopadhyay-Ghosh
Polyelectrolytes are used to synthesize hydrogels that are sensitive to electric field or current. They swell or shrink upon application of an electric field. Partially hydrolyzed polyacrylamide hydrogels in contact with electrodes, for example, undergo phase transition by a change in electric potential across the gel (Gupta and Siddiqui 2012).
Recent advances in polymeric materials for the delivery of RNA therapeutics
Published in Expert Opinion on Drug Delivery, 2019
David Ulkoski, Annette Bak, John T. Wilson, Venkata R. Krishnamurthy
All polymers that bear cationic and/or anionic charges under physiological conditions can be considered polyelectrolytes. In contrast, zwitterionic polymers such as polyampholytes consist of both cationic and anionic groups along the main or side chain. Charge stoichiometry of polyions can be balanced the produce neutral, cationic, or anionic character. The interactions between acidic and basic groups establish zwitterionic properties that minimize the net charge to mitigate charge-related toxicities that exist with purely cationic polyelectrolytes [237]. These polymers are typically responsive to multiple stimuli, converting between anti-polyelectrolyte or polyelectrolyte characteristics within different environmental conditions. When the zwitterionic linkages are subjected to intracellular pH, bond dissociation and net charge increase can occur, allowing for endosomal escape and payload release [238–240].
Complexation of novel thiomers and insulin to protect against in vitro enzymatic degradation – towards oral insulin delivery
Published in Drug Development and Industrial Pharmacy, 2019
C.O. Ibie, R.M. Knott, C.J. Thompson
Recent advances in the design of functional polymeric drug delivery systems have led to the utilization of polyelectrolyte complexes (PECS) for protein delivery. PECS are formed spontaneously by electrostatic interaction between oppositely charged polyelectrolytes (i.e. a polymer and protein) in aqueous solution [10, 11]. Indeed, PECS containing insulin and other proteins have already been the subject of research by a number of groups [11–16]. These complexes are typically positively charged nanoparticles, with hydrodynamic sizes between 100–400 nm in aqueous media. Polyelectrolyte complexation has the advantage of being a more benign process than other methods of manufacturing nanoparticles, which usually require the use of aggressive processing conditions and organic solvents. Formulation of proteins as PECS can also impart improved characteristics, i.e. enhanced absorption and reduced degradation, via modification to the polymeric carrier, rather than to the protein itself; thereby, preserving the original structure of the protein [15]. Hence, rational optimization of polymer structure to provide a robust network to facilitate optimum complexation, enzymatic protection, and GI absorption of proteins is required.
Synthetic Toll-like receptor agonists for the development of powerful malaria vaccines: a patent review
Published in Expert Opinion on Therapeutic Patents, 2018
Arshpreet Kaur, Deepika Kannan, Surinder K. Mehta, Shailja Singh, Deepak B. Salunke
Polyelectrolyte multilayers are widely employed in various fields such as catalysis, sensing, and drug delivery systems [43]. These materials are generally prepared by layer-by-layer self assembly (LbL) formation of oppositely charged polyelectrolytes to create ordered, well-arranged multilayer structures. The driving force for such ordered array of layers is electrostatic force between successive layers [44]. These multilayers have been recently used as vaccine carriers as they absorb or encapsulate vaccine components on or within multilayers composed of polymers [45] and these polymeric capsules have given exciting approach to overcome cancer and other viral pathogens [46]. Polypeptide multilayer films composed of at least one layer of charged polypeptide are referred as designed polypeptides (DPs).