POLYETHYLENEIMINE Chemische Eigenschaften,Einsatz,Produktion Methoden
Chemische Eigenschaften
Clear viscous liquid
Verwenden
Polyethyleneimine is used as a polyelectrolyte multilayer on charged surfaces to provide a biocompatible coating on surfaces.1Detergents, adhesives, water treatment, printing inks, dyes, cosmetics, and paper industry, adhesion promoter, lamination primer, fixative agent, flocculant, cationic dispersant, stability enhancer, surface activator, chelating agent, scavenger for aldehydes and oxides.
Application
Polyethyleneimine(PEI) can be used as a non-viral synthetic polymer carrier for in vivo delivery of therapeutic nucleic acids. The interaction between the negatively charged nucleic acid and the positively charged polymer backbone leads to the formation of nanoscale complexes. This neutralising complex protects the enclosed nucleic acid from enzymes and maintains its stability until cellular uptake occurs. For example, human serum albumin-coupled PEI shows good pDNA transfection and low toxicity.
PEI can be used to functionalize single-walled nanotubes (SWNTs) to improve their solubility and biocompatibility while maintaining the structural integrity of the original SWNT. Covalently functionalized SWNTs can be used for CO2 uptake and gene delivery.
Branched PEI can also be used to modify the surface properties of adsorbents. PEI-modified aqueous zirconia/PAN nanofibres have a high fluoride adsorption capacity and a wide working pH range, and can therefore be used for groundwater defluoridation.
Vorbereitung Methode
Polyethylenimine is produced by the homopolymerization of ethylenimine. The reaction is catalyzed by acids, Lewisacids, or haloalkanes. The polymerization is usually carried out at 90 – 110 ℃ in water or in a variety of organic solvents. The average molecular mass of the polyethylenimine prepared as described above is 10 000 – 20 000. Higher molecular mass polymers are prepared by addition of a difunctional alkylating agent, such as chloromethyloxirane or 1,2-dichloroethane. Polyethylenimines with a higher average molecular mass can also be provided by ultrafiltration of polymers with a broad mass distribution. Likewise, polymers of lower molecular mass can be obtained by inclusion of a low molecular mass amine, such as 1,2- ethanediamine, during polymerization. By using these techniques a range of molecular masses from 300 to 10 6 can be obtained. Cross-linking during the polymerization of ethylenimine in organic solvents leads to solid polyethylenimines. Furthermore the polymerization process can be conducted on the surface of organic or inorganic materials, thus fixing the polyethylenimines to a support.
Allgemeine Beschreibung
All polyethylene imine polymers are hydrophilic and may contain approx. 30% hydrated water.
Handelsname
Lupasol, Polymin, Catiofast, Lugalvan (BASF), Epomin (Nippon Shokubai).
Biologische Aktivität
Polyethylenimine is nondegradable and the molecular weight of PEI affects the cytotoxicity and gene transfer activity. Polyethylenimine acts as a low toxicity and efficient gene vector.
Structure and conformation
Polyethyleneimine(PEI) exists as both a branched and linear structure. Branched PEI (bPEI) is synthesized via acid-catalyzed polymerization of aziridine, whereas the linear structure (lPEI) is synthesized via ring opening polymerization of 2-ethyl-2-oxazoline followed by hydrolysis.
POLYETHYLENEIMINE Upstream-Materialien And Downstream Produkte
Upstream-Materialien
Downstream Produkte
