Dextran methacrylate

Fig. 20 Synthesis of dextran methacrylate usable for the formation of hydrogels after photo-initiated cross-linking [175]...

Fig. 21 Three-dimensional porous structure of a dextran methacrylate hydrogel observed by means of SEM...

Transparent hydrogels useful for adhesion inhibitors, tissue adhesives, wound dressings, hemostatics and embolisation materials are obtained from dextran methacrylates via polymerisation with N-isopropylacrylamide in DMSO in the presence of azobisisobutyronitrile [176]. A broad variety of new hydrogels with different sensitivities and tunable degradation behaviour is accessible by grafting L-lactide onto 2-hydroxyethyl methacrylate (HEMA) and binding this polymerisable group on dextran via activation with N,N -carbonyldiimidazole (CDI, Sect. 4.2.2) [177]. 

De Smedt S, Meyvis E, van Oostveldt P, Blonk J, Hennink W, Demeester J. The diffusion of macromolecules in dextran methacrylate solutions and gels as studied by confocal scanning laser microscopy. Macromolecules 1997, 30, 4863-4870. 

Klinger, D., Aschenbrenner, E. M., Weiss, C. K. and Landfester, K. (2012). Enzymatically degradable nanogels by inverse miniemnlsion copolymerization of acrylamide with dextran methacrylates as crosslinkers. Polymer Chemistry, 3,204-216. 

Kim, S., Chu, C.C. Pore structure analysis of swollen dextran-methacrylate hydrogels by SEM and mercury intrusion porosimetry. J. Biomed. Mater. Res. 2000(53), 258... 

Sahota, T., Tomlins, R, Taylor, M.J., 2015. Long-term stability of glucose responsive dextran methacrylate-concanavalin A methacrylamide gels as part of an implantable artificial pancreas. Int. J. Polym. Mater. Polym. Biomater. 64 (18), 946-954. 

Cationic hydrophilic Glycol chitosan, DEAE-dextran, poly(ethyleneimine), poly(trimethylaminoethyl methacrylate) iodide salt 0.5 M acetic acid with 0.3 M NaiSO, or 0.8 M NaNO.,... 

Figure 17 Permeability of uranine ( ), dextran 4.4K (O), and dextran 150K (A) through cross-linked poly(/V-isopropyl acrylamide-co-butyl methacrylate, 95 5 mol%) membrane. Error bars represent standard deviation in the slope of the curve of the receiver concentration of solute as a function of time at steady state. (From Ref. 37.)...

Jiang and Zhu (2000) and Qiu and Zhu (2001) have reported the fabrication of multilayered devices composed of stacks of compression-molded disks of alternating compositions. One type of disk is either P(SA-EG) or P[SA-co-TMAgly)-Z>-EG] and the other is a pH-sensitive, protein-loaded blend of, for example, poly(methacrylic acid) and polyethoxazoline. The release of model proteins, myoglobin, bovine serum albumin, and FITC-dextran, and compounds such as brilliant blue have been studied and pulsatile release profiles have been demonstrated (Jiang and Zhu, 2000 Qiu and Zhu, 2001). 

Avseenko et al. (2001) immobilized antigens onto aluminum-coated Mylar films by electrospray (ES) deposition. Various surface modifications of the metallized films were studied to determine their abilities to enhance sensitivity. The plastic surfaces were firsf cleaned by plasma discharge treatment, followed by coating with proteins (BSA and casein) or polymers such as poly (methyl methacrylate) or oxidized dextran, or they were exposed to dichlorodimethyl silane to create hydrophobic surfaces. Protein antigen was prepared in 10-fold excess sucrose and sprayed onto the surfaces to form arrays with spot diameters between 7 and 15 pm containing 1 to 4 pg protein. 

Significant research has been directed toward the use of polyelectrolyte complexes as blood compatible materials. Several investigators found that water-insoluble polyelectrolyte complexes can suppress blood coagulation [487-490]. Davison and coworkers reviewed and studied the biological properties of water-soluble polyelectrolyte complexes [491] between quatemized poly(vinyl imidazole) or polyvinyl pyridine) and excess sulfonated dextran or poly(methacrylic acid). By forming complexes with a stoichiometric excess of anionic charge, a more compact conformation with anionic character was obtained. 

Commonly employed water-insoluble supports for the covalent attachment of enzymes include synthetic supports such as acrylamide-based polymers, maleic anhydride-based polymers, methacrylic acid-based polymers, styrene-based polymers, and polypeptides, and natural supports such as agarose (Sepharose), cellulose, dextran (Sephadex), glass, and starch (Zaborsky, 1973). 

DDMC 2-Diethyl-aminoethyl-dextran-methyl methacrylate graft copolymer... 

Onishi Y, Eshita Y, Murashita A et al (2005) Synthesis and characterization of 2-diethyl-aminoethyl-dextran-methyl methacrylate graft copolymer for nonviral gene delivery vector. J Appl Polym Sci 98 9-14... 

Hydroxyethyl methacrylate Human immunodeficiency virus 1,1,1,3,3,3,-Hexamethyldisilazane Hydrophobically modified polycationic dextran Heteronuclear multiple quantum correlation High performance liquid chromatography Herpes simplex virus... 

Interestingly, CDI can also be utilised for the introduction of substituents by inter- or intramolecular coupling of OH moieties of the polysaccharide via a carbonate function. This synthesis was used to obtain dextran with 2-hydroxyethyl methacrylate moieties (dex-HEMA) and dex-HEMA with lactate spacer functions (Fig. 32). A new class of dextran derivatives (DS < 0.2) that can be polymerised containing hydrolysable groups is accessible [177]. 

Fig. 32 Conversion of dextran with hydroxyethyl methacrylate lactate using CDI yielding a carbonate-bound ester moiety...

Passirani, C., L. Ferrarini, et al. (1999). Preparation and characterization of nanoparticles bearing heparin or dextran covalently-linked to poly(methyl methacrylate). J Biomater Sci Polym Ed 10(1) 47-62. 

Columns of dextran have been prepared with a more elaborate procedure.13 It is claimed that the EOF has been eliminated and that columns are very stable under very harsh conditions, e.g., 0.05 M NaOH with 5% SDS or 1 M HC1. Cellulose-coated capillaries have been prepared by coupling 2-hydroxyethyl methacrylate (HEMA)-derivatized hydroxypropyl cellulose (HPC) to columns derivatized with 7-oct-l-enyltrimethoxysilane.The coating was stable for several weeks in the pH range from 2 to 10 and diminished the EOF, and it has been found useful for separation of peptides, glycoproteins, and derivatized oligosaccharides. 

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