Polyurethane nanoparticles synthesis

Multifunctional biotinylated and streptavidin-coated polyurethane-urea nanoparticles have also been engineered from OAV nano-emulsions." " In these studies, biotin or streptavidin reacts with diisocyanate at the droplet interface and are successfully attached to the nanoparticle polymeric matrices. These nanoparticles exhibit diameters around 110-140mn (biotin nanoparticles) and 70-74nm (streptavidin nanoparticles). In addition, streptavidin-coated polyurethane-urea nanoparticles were functionalized with biotin anti-VCAM-1 and anti-ICAM-1 antibodies for specific targeting. Both nanoparticulate systems showed no cytotoxicity in healthy endothelial cells and therefore good biocompatibility properties. Figure 7.1 shows a schema of the synthesis of different polyurethane nanoparticles obtained from 0/W nano-emulsions by interfacial polymerization and images obtained by transmission electron microscopy. 

The formation of polyurethane nanoparticles from inverse nano-emulsions (W/O) has also been achieved. Interfacial polyaddition in inverse nano-emulsion is of special interest since this allows the encapsulation of hydrophilic active materials such as proteins or nucleic acids. Thus, taking advantage of the high reactivity of tolylene 2,4-diisocyanate with water molecules, polyurea lipid nanocapsules with aqueous cores obtained from W/O nano-emulsions and prepared by PIT method were designed. Polymer synthesis occurs by in situ interfacial polymerization after nano-emulsion formation. Volatile oils employed as the continuous phase were removed by evaporation and the nanocapsules were redispersed in water. These nanocapsules could be potentially used for encapsulation of both hydrophilic and lipophilic molecules simultaneously. 

Other Synthetic Biodegradable Polymers Although well investigated for drug delivery, polyorthoesters, polyurethanes, and polyamides have found limited application as nanoparticles. A report documents the synthesis and characterization of polyorthoester nanoparticles [105],... 

Cheong I, Kim J. Synthesis of core-shell polyurethane-urea nanoparticles containing 4,4 -methylenedi-p-phenyl diisocyanate and isophorone diisocyanate by self-assembled neutralization emulsification. Chem Commun 2004 21 2484-5. 

Table 7.1 Synthesis aspects of polyurethane and polyurea nanoparticles obtained from OAV nano-emulsions... 

Chemical reduction is the most frequently applied method for the preparation of silver nanoparticles as stable, colloidal dispersions in water or organic solvents. However, a number of alternative green chemistry synthesis routes have been reported. Inspired by mussel adhesive proteins, a novel functional polyurethane based on hydrolyzable tannins that contain a number of catechol groups was... 

Saez S, Fasciani C, Stamplecoskie K, Gagnon LBP, Mah T-F, Marin ML, et al. Photochemical synthesis of biocompatible and antibacterial silver nanoparticles embedded within polyurethane polymers. Photochem Photobiol Sci 2015 14(4). http //dx.doi.oig/ 10.1039/c4pp00404c. in publishing. 

We synthesized nanohydrogel polyurethanes with Cloisite 30B organically modified clay nanoparticles of montmorillonite to obtain hybrid materials possessing great swelling properties. These materials were studied by XRD, DMA, and water absorption capacity measurements. The synthesis procedure yielded stable and homogeneous hydrogel materials. Addition of clay nanoparticles causes an increase in the absorptivity of water molecules in the polyurethane matrix. 

In addition to the synthesis of latexes with high solids content and small particle size, in the past decade, microemulsion polymerization has heen used to synthesize a wide range of materials. For instance, several works have incorporated inorganic materials such as carhon nanotuhes, " ZnO nanoparticles (UV absorption),montmorillonite clay, " and quantum dots (luminescence probes) " to produce nanocomposites. Furthermore, nanogels, " conductive polypyrrole and polyaniline latexes, " " polyurethanes using immiscible monomers, and polymers in water-in-scC02 microemulsions have been also prepared by microemulsion polymerization. 

Wang J, Raza A, Si Y, Ciri L, Ge J, Ding B, Yu J (2012) Synthesis of superamphiphobic breathable membranes utilizing Si02 nanoparticles decorated fluorinated polyurethane nanofibers. Nanoscale 4(23) 7549 7556. doi 10.1039/c2nr32883f... 

Mahfuz H, Rangari VK, Islam MS, Jeelani S. Fabrication, synthesis and mechanical characterization of nanoparticles infused polyurethane foams. Compos A Appl Sci Manuf 2004 35 453-60. 

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