PEG surface coatings

For protein immobilization the most commonly used method is the EDC-NHS affinity ligand coupling chemistry as described for DNA bonding to glass substrates. An advanced surface coating method for protein microarrays was developed by the company MicroSurfaces. A polyiethylene glycol) (PEG) surface coating. 

Finally, nanomaterials can be deposited ( settle ) in different organs, such as the liver, spleen, vasculature, heart and bone marrow [14, 35, 51, 84]. Most nanomaterials deposited in the liver were engulfed by Kupffer cells [51]. The deposition location appears to be affected by the nanomaterials surface coating for example, a PEG surface coating can prevent the uptake of nanoparticles by hepatic and splenic cells [90]. On occasion, for drug delivery purposes, an intentional surface coating is required. For example, the delivery of nanomaterials to the brain is extremely difficult, although a specific receptor, apolipoprotein, has been used to facilitate such translocation [16, 20, 91, 92]. 

Figure 6.33 Zyomyx s b-SAM and PLL-PEG-biotin surface coatings. (From Nock, S. and Wilson, D.S., Angew. Chem. Int. Ed., 42, 494-500, 2003. With permission.)...

FIGURE 9 (a) Clearance from circulation and (b) accumulation in liver and spleen of liposomes composed of lecithin (LS) mixed or not with charged lipids (PS = phosphadityl serine, PA = phosphatidic acid, SA = stearylamine) and bearing or not, a surface coating with PEG molecules after IV administration (PEG-750 and PEG-5000 = polyethylene glycol with molecular weights 750 and 5000). (Reproduced from ref. 230 with permission of Elsevier.)... 

In addition to PEG, certain polysaccharides, such as hyaluronic acid (HA) and dextran, have been used as low protein-adsorption, low cell adhesion surface coatings. Synthetic polymer surfactants consisting of poly(vinyl amine) with dextran and alkanoyl side chains, which mimicks the glycocalyx—negatively charged sugar layer outside cell membrane, are also shown to reduce protein adsorption to hydrophobic graphite surface. ... 

To bring the nanocontainer to a specific place where it should release its pay-load, targeting is a required approach. Hence, much work has been carried out to attach ligands or antibodies to the hydroxyl end-group of PEG-based assemblies [150,181,243], Biotinylated nondegradable block copolymer assemblies have been shown to attach to surfaces coated with the biotin receptor avidin [146,147, 150,244], Coupling chemistry has been applied to conjugate either an antihuman IgG, or antihuman serum to PEG-carbonate- or PEG-polyester-assembled polymer vesicles [149,245], HIV-derived Tat peptide attached to PEG-PBD polymersomes enhanced the cellular delivery of nanoparticles [246] and increased dendritic cell uptake in vitro [181]. 

Ethylan TN10 PEG-10 cocamine wetting agent, surface coatings... 

PEGylation is also the most widely used bioinert polymeric surface coating currently used [39]. Although it is considered as a gold standard for protein-resistant surfaces, recent observations indicate that PEGylation is far from being the optimal candidate for biomedical applications. Even though PEG is... 

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