Synthetic hydrogels

Barbetta Andrea, Elena Barigelli, and Mariella Dentini. Porous alginate hydrogels Synthetic methods for tailoring the porous texture. Biomacromolecules. 10 no. 8 (2009) 2328-2337. 

Whiteside, N.J., Wallace, C.C., Panhuis, M.I.H., 2013. Preparation and characterisation of graphene composite hydrogels. Synthetic Metals 168, 36—42. 

Hydrogels, ie, gelatin and agar, have been known for a long time. In the late nineteenth century, Herschel proposed the use of jelly materials on the cornea for the correction of vision (108). In 1960, the use of synthetic hydrogels for contact lenses was proposed and several U.S. patents were obtained for the invention of cross-linked hydrophilic polymers, eg, systems based on 2-hydroxethyl methacrylate [868-77-9] (HEMA) (5) (109—112). 

Fig. 5. Scanning electron micrographs of hoUow fiber dialysis membranes. Membranes in left panels are prepared from regenerated cellulose (Cuprophan) and those on the right from a copolymer of polyacrylonitrile. The ceUulosic materials are hydrogels and the synthetic thermoplastic forms a microreticulated open cell foam with a tight skin on the inner wall. Pictures at top are membrane cross sections those below are of the wall region. Dimensions as indicated.

WangC, Stewart RJ, Kopecek J (1999) Hybrid hydrogels assembled from synthetic polymers and coiled-coil protein domains. Nature 397 417-420... 

Lutolf MP, Lauer-Fields JL, Schmoekel HG et al (2003) Synthetic matrix metalloproteinase-sensitive hydrogels for the conduction of tissue regeneration Engineering cell-invasion characteristics. Proc Natl Acad Sci 100 5413-5418... 

In the most succinct sense, a hydrogel is simply a hydrophilic polymeric network cross-linked in some fashion to produce an elastic structure. Thus any technique which can be used to create a cross-linked polymer can be used to produce a hydrogel. Copolymerization/cross-linking free radical polymerizations are commonly used to produce hydrogels by reacting hydrophilic monomers with multifunctional cross-linkers. Water-soluble linear polymers of both natural and synthetic origin are cross-linked to form hydrogels in a number of ways ... 

The most common and most versatile technique for the production of synthetic hydrogels is the free radical (chain) copolymerization of monofunctional and multifunctional vinyl monomers. Gels can also be created by the step (e.g., con-... 

PI Lee. Synthetic hydrogels for drug delivery Preparation, characterization and release characteristics. In DST Hsieh, ed. Controlled Release Systems Fabrication Technology, Vol II. Boca Raton, FL CRC Press, 1988, pp 83-110. 

BD Ratner, AS Hoffman. Synthetic hydrogels for biomedical applications. In JD Andrade, ed. Hydrogels for Medical and Related Applications. ACS Symp Ser 31. New York American Chemical Society, 1976, pp 1-36. 

WR Gombotz, AS Hoffman. Immobilization of biomolecules and cells on and within synthetic polymer hydrogels. In NA Peppas, ed. Hydrogels in Medicine and Pharmacy, Vol I. Boca Raton, FL CRC Press, 1986, pp 95-126. 

We have emphasized here that the dynamic aspects of NMR studies are crucially important for structurally or dynamically heterogeneous systems such as synthetic or natural hydrogels, protein fibrils and membrane proteins. This is in order to characterize their unique chemical, physical and biological properties in terms of a variety of fluctuation frequencies, including high (> 108 Hz) or intermediate (104-105 Hz) frequency fluctuations. It turns out that the presence of the high-frequency motions, which are readily evaluated by comparative CPMAS and DDMAS studies, is... 

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