Polycationic polymer

Polycationic polymers. These are macromolecules that have electropositive groups attached to the polymer chain or pendant to the chain. These materials are active against a number of bacteria and fungi. However, due to their inherent toxicity to animal species through their destructive interaction with cell membranes they are... 

Hong S, Leroueil PR, Janus EK, et al. (2006). Interaction of polycationic polymers with supported lipid bilayers and cells nanoscale hole formation and enhanced membrane permeability. Bioconjug. Chem. 17 728-34. 

Figure 3.21 The design of dynamic nncleic acid analogs 8 and 9, or DyNAs, for dynamic acylhydrazone formation with A-C to develop polycationic polymers.

One of the most important criteria of transfection with polycationic polymers is the ability of the polymer to condense plasmid DNA. Naked DNA can be taken up by cells and expressed, however not at sufficiently high levels, presumably due to degradation at one or multiple points in the transfection process. In solution,... 

Chemical structures of polycationic polymers used as gene delivery vectors 339... 

Guidelines for design of nontoxic polycationic polymers for gene delivery 351... 

Abstract In the late 1980s independent work by Feigner and Behr pioneered the use of cationic materials to complex and deliver nucleic acids into eukaryotic cells. Since this time, a vast number of synthetic transfection vectors, which are typically divided into two main transfectors , have been developed namely (1) cationic lipids and (2) polycationic polymers. In this chapter the main synthetic approaches used for the synthesis of these compounds will be reviewed with particular attention paid to cationic lipids and dendrimers. This review is aimed primarily at the younger audience of doctoral students and non-specialist readers. 

Lim Y, Choi YH, Park J (1999) A self-destroying polycationic polymer biodegradable poly (4-hydroxy-L-proline ester). J Am Chem Soc 121 5633-5639... 

Chitosan, a biocompatible and biodegradable polycationic polymer with low toxicity, is known for its swelling ability and permeation-enhancing properties and represents a polymer of choice for the preparation of microspheres intended for nasal administration [74],... 

Fasbender A, Zabner J, Chillon M, Moninger TO, Puga AP, Davidson BL, Welsh MJ. Complexes of adenovirus with polycationic polymers and cationic lipids increase the efficiency of gene transfer in vitro and in vivo. J Biol Chem 1997, 272, 6479-6489. 

Scientists at MIT and Tufts University have demonstrated that covalent attachment of N-alkylated poly (4-vittylpy ridine) (PVP) to glass surfaces makes the surfaces lethal to several types of bacteria on contact. PVP and other polycationic polymers in solution can kill bacteria by dismpting bacterial cell membranes. The scientists have found a fairly narrow range of N-alkylated PVP compositions that allow the polymers to retain their bacteria-killing ability when coated on dry surfaces. The group hopes to demonstrate that any common surface, whether its PVC, PE, metals, ceramics, wood or fabrics, can use this kind of derivatisation to make that surface capable of killing airborne bacteria. 

PatentNumber US 5616317 A 19970401 POLYCATIONIC POLYMER AND POLYCATIONIC MICROBIOCIDALAND ALGAECIDAL AGENT... 

We now consider the effect of electrostatics on initial adsorption rates. Our first example [26] is again for the polycationic polymer PVP+ adsorbing at pH 8 on Ti02, which is negatively charged under these conditions see Figure 5. It is the same system as considered in Figure lb. Two sets of... 

Gelation of polyanionic or polycationic polymers by the addition of multi-valent counter-ions is a simple and common method of entrapment of enzymes and whole cells. In one common embodiment, whole cells or enzymes are entrapped by the drop-wise addition of an aqueous solution of sodium alginate and the biocatalyst to a concentrated solution of a Ca2+ salt. The cation acts as a cross-linking agent towards the alginate biopolymer and the droplets precipitate as beads with the biocatalysts entrapped within the network. Although the beads are relatively soft and unstable, this method has been one of the preferred methods for entrapment of whole cells. A... 

Representation of an enzyme electrode based on glucose oxidase (containing FADH2 centers) and a polycationic polymer incorporating redox groups, R. (b) The electron-transfer steps in the reaction, with approximate potentials of the electrode and the redox couples. [Reprinted with permission from A. Heller, Acct5. Chem. Res., 23, 128 (1990). Copyright 1990, American Chemical Society.]... 

The consecutive layer-by-layer adsorption of polyanions and polycations built on glass or silicon wafers first (by chemisorption) with a monolayer of positively charged poly(ethyleneimine) (PEI) was recently reported [47]. Analogous hybrid multilayer architectures were prepared in which polycationic polymers... 

Polybrene (PB) has been used to prepare physically adsorbed polymeric coatings [59,60]. PB is a polycationic polymer, composed of quaternary amines (V,V,V, V -tetramethyl-l,3-propylenediamine), which strongly adsorbs to the inner surface of the capillary and reverses the... 

Huguet, M.L. Neufeld, R. J. Dellacherie, E. Calcium-alginate beads coated with polycationic polymers Comparison of chitosan and DEAE-dextran. Process Biochem. 1996, 31 (4), 347-353. 

Regardless of the type of targeting agent, carrier molecules can be subdivided into three classes on the basis of their characteristic length [243] nano-, micro-, and macroscale vectors. In general, nanoscale vectors are represented by polycationic polymers or lipids that self-assemble with NABD to form polyelectrolyte complexes. Microscale vectors usually consist of NABD entrapped within a polymeric matrix, and macroscale vectors are 2D/3D scaffolds or matrices (mainly polymeric but not only) hosting the desired NABD. Of course, it is possible to embed nano-/microscale vectors inside macroscale vectors. Nano-/microscale vectors protect NABD and favor the cellular internalization, while macroscale vectors can modulate nano-/microscale vector release kinetics at the site of action (Figure 15.24). 

The slow threading kinetics are a result of the high complex stability between cucurbituril and protonated hexane diamine derivatives. Wenz et al. made a very similar observation while studying the threading of various cyclodextrins along a polycationic polymer chain. ° ° Maximum levels of threading were established only after many weeks. They successfully modelled their post-threading system... 

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