Polyethyleneimine, PEI

Alpert and Regnier [37] found that polyethyleneimine (PEI, M = 600) was readily adsorbed by various porous silicas from a methanol solution. After the reversibly adsorbed portion of the polymer was washed out, the content of... 

Fig. 1. Competition binding screens Bead/ligand compatibility test in early assay development. The beads PVT-WGA, Type A and Type B are based on polyvinyltoluene (PVT) not polyethyleneimine (PEI). PVT, polyvinyltoluene WGA, wheat germ agglutinin Ysi, yttrium silicate.

Fluorescent nanotubes of polyethyleneimine (PEI) and 3,4,9,10-perylenetetra-carboxylicdianhydride (PTCDA) have been prepared through the alternating deposition of polymers and small functional molecules that form covalent bonds (Figure 7.10) [ 120]. The nanotube synthesis starts with the deposition of P EI in the pores of an AAO membrane as the first layer. The PTCDA solutionis then used to bind to the PEI via covalent bonding (Figure 7.10). The electro-optical properties of the small molecule (PTCDA) are retained in the multilayer films of PEI/PTCDA. The prepared nanotubes retain their fluorescent properties for up to 10 months without... 

Polyethyleneimine (PEI), 16 14, 15 molecular formula, 5 713t Polyethylene ionomers, properties of, 14 413—415... 

Figure 6.10 Influence of molecular weight on the adsorption of polyethyleneimines (PEI) by a bleached sulfite pulp (PEI 10 = DP of 10 and PEI 500 = DP 500).

Bulky, partially charged ligands (polyelectrolytes), e.g., polyethyleneimine (PEI) [40]... 

Cell debris may be removed by centrifugation at 10,000 g for 30 min. The nucleic acids being the major contaminant can be removed by precipitation with a positively-charged pol)uner such as polyethyleneimine PEI (t)q)ically 0.5-1% of a 10% solution). Addition of magnesium to the resuspension buffer will assist in the enzyme digestion of DNA by DNAse. Some loss of protein may occur by copreciptation, which is especially the case with some DNA-binding proteins. This can usually be avoided by a 1 1 dilution of the crude extract with buffer. 

Gold nanoparticles can also be stabilized using polymers that do not have specific functional groups through physisorption. Among the possible stabilizers, the polymers used most often to stabilize Au NPs are the water soluble polymers poly(N-vinylpyrrolidone) (PVP), polyethylene glycol) (PEG), poly(vinyl pyridine), poly(vinyl alcohol) (PVA), poly(vinyl methyl ether) (PVME), and polyelectrolytes such as PAA, chitosan, polyethyleneimine (PEI) or poly(diallyl dimethylammonium) chloride (PDDA) [99]. 

Figure 10.8 Chemical structures of positively charged polyethyleneimine (PEI), polyallyl-aminhydrochlorid (PAH), polylysine hydrobromide (PL) and negatively charged polystyrene-sulfonate (PSS). M+ denotes a metal ion such as Na+.

Paredes et al. [15] Fructose Honey Fruit juices Soft drinks D-PQQ-fructose dehydrogenase/physically included in the electrode matrix, also containing mediator and polyethyleneimine (PEI) Carbon paste electrode/ 0.1 V vs. Ag/AgCl Os(bpy)2Cl2 (included in the electrode matrix)... 

Polyethyleneimine (PEI) (branched) Randomly branched, primary, secondary, and tertiary amino groups In vitro and in vivo transfections, including therapeutic genes (Boussif et al., 1995)... 

Cationic polymer is also frequently examined to increase the potential of a gene drug. Large molecular weight cationic polymers can condense pDNA more efficiently than cationic liposomes. They include poly-L-lysine (PLL), poly-L-omithine, polyethyleneimine (PEI), chitosan, starburst dendrimer and various novel synthetic polymers. These polymers can enhance the cellular uptake of pDNA by nonspecific adsorptive endocytosis. 

Peptide-based gene delivery, 334 Peptide nucleic acid (PNA), 73,252 Pharmacokinetics, 409 Polyethyleneimine (PEI), 369 Peptides with thiol groups, 348 Persistence of gene expression, 10,463 Physiological Pharmacokinetics, 423 PNA binding affinity, 75 Poly anion interchange, 179 Poly cations, 164 Polymeric gel, 447 Polyamidoamine (PAMAM), 376 Polyaminomethacrylates, 379 Poly(L-lysine), 336, 369 Poly(vinyl pyrrolidone) (PVP), 382 Prophylactic vaccines, 474... 

Process development with Brevibacterium ammoniagenes (introduced in 1974), similarly to the development in the i-aspartate process led to 25-fold improvements, mainly through use of a Brevibacteriumflavum strain immobilized on ic-carrageenan gel with polyethyleneimine (PEI) crosslinker, so that a half life of 310 days at 37°C has been achieved. 

Polyethyleneimine (PEI) (with reporter dendrimer-phthalocyanine TPPS2a, AlPcS2a... 

DNA has been embedded in LbL films by assembling with polycations like PLL, polyethyleneimine (PEI), and poly(dimethyldiallylammonium chloride) (PDAD) [38-42]. Zhang showed that the DNA released from the film with synthetic degradable polyamine is transcriptionally viable [41]. DNA molecules can keep their structure when incorporated in the film with synthetic polymers [39], making films with DNA suitable candidates for gene delivery. 

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