Bioactivity polyelectrolytes

A third approach to prepare HA-taxol conjugate involves a labile succinate ester (Fig. 4). These hydrophobic PTX conjugates were amenable to the preparation of multilayer macromolecular assemblies of bioactive polyelectrolytes (38). 

The synthesis of polypyrrole-heparin nanotubes was performed at a constant potential of 0.8 V (vs. SCE), using a nanoporous membrane as a template [71]. Heparin, which is a bioactive polyelectrolyte, was used as the doping anion. The use of a bioactive doping compound, which provides interesting biological properties in the composite sample, allows the fabrication of functionalized surfaces able to promote direct electronic communication between biological species and substrates. This result also confirmed that the... 

Many polymer-polymer complexes can be obtained by template polymerization. Applications of polyelectrolyte complexes are in membranes, battery separators, biomedical materials, etc. It can be predicted that the potential application of template polymerization products is in obtaining membranes with a better ordered structure than it is possible to obtain by mixing the components. The examples of such membranes from crosslinked polyCethylene glycol) and polyCacrylic acid) were described by Nishi and Kotaka. The membranes can be used as so-called chemical valves for medical applications. The membranes are permeable or impermeable for bioactive substances, depending on pH. 

Besides the bioactivity, dextran sulfate was studied for a broad variety of applications using its polyelectrolyte nature and its ability to form polyelec-... 

Thierry B, Winnik FM, Merhi Y et al, Bioactive coatings of endovascular stents based on polyelectrolyte multilayers. Biomacromolecules 2003 4 1564-1571. 

Keywords Bioactive Layer-by-layer Multilayered films Polyelectrolyte self-assembly Remote release... 

Protein aggregates [107, 109, 121] or dye crystals [122-126] can serve as templates for LbL polyelectrolyte adsorption. Chymotrypsin aggregates encapsulated by PSS and PAH deposition contain a high protein amount and the enzyme keeps its bioactivity [107], The aggregates prepared in this manner have high incorporation efficiency and a protein content of 50-70% [109]. An encapsulated catalase has been shown to be stable against protease degradation [121],... 

Jessel N, Atalar F, Lavalle P et al (2003) Bioactive coating based on a polyelectrolyte multilayer architecture functionalized by embedded proteins. Adv Mater 15 692-695... 

Schneider A, Vodouhe C, Richert L et al (2007) Multifunctional polyelectrolyte multilayer films combining mechanical resistance, biodegradability, and bioactivity. Biomacromolecules 8 139-145... 

One of the best-known examples of this class is interferon (a glycoprotein), which has shown much promise as an antiviral agent and in the treatment of cancer (71). Numerous polymers (mostly polyelectrolytes) are effective in inducing the production of interferon in animals (72). Other well-known bioactive polypeptides are insulin, adrenocorticotropic hormone (ACTH), human growth hormone (HGH), prolactin, follicle stimulating hormone (FSH), and luteinizing hormone most of these have been synthesized, and some derivatives have been prepared (73). Some small bioactive polypeptides are the nonapeptides bradykinin, vasopressin, and oxytocin bioactive derivatives have been made for many of these also (74). 

Adsorption and release of dyes in PEMs is a perspective direction for development of new bioactive films with prolonged action. By varying PEMs structure, conditions of their formation, thickness, and also using various polyelectrolytes, it is possible to achieve the high dye loading and proper control of its release. 

Delair T (2011) Colloidal polyelectrolyte complexes of chitosan and dextran sulfate towards versatile nanocarriers of bioactive molecules. Eur J Pharm Biopharm 78 10-18... 

Li QL, Wu MY, Tang LL et al (2008) Bioactivity of a novel nano-composite of hydroxyapatite and chitosan-phosphorylated chitosan polyelectrolyte complex. J Bioact Compat Polym... 

Wang Y, Hong Q, Chen Y, LianX,Xiong Y. Snrface properties of polynrethanes modified by bioactive polysaccharide-based polyelectrolyte multilayers. Colloids Surf B Biointerfaces lOUAdOJl-S3. http //dx.doi.Org/10.1016/j.colsurfb.2012.05.030. 

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