Poly bioactivities

Allcock HR. Qrganometallic and bioactive phosphazenes. J Polym Sci Polym Symp, 1983, 70, 71-77. Allcock HR. Poly(organophosphazenes) Synthesis, unique properties and applications. Makromol Chem... 

The next two examples illustrate more complex surface reaction chemistry that brings about the covalent immobilization of bioactive species such as enzymes and catecholamines. Poly [bis (phenoxy)-phosphazene] (compound 1 ) can be used to coat particles of porous alumina with a high-surface-area film of the polymer (23). A scanning electron micrograph of the surface of a coated particle is shown in Fig. 3. The polymer surface is then nitrated and the arylnitro groups reduced to arylamino units. These then provided reactive sites for the immobilization of enzymes, as shown in Scheme III. 

Kohn, J., and Langer, R., Non-peptide poly(amino acids) for biodegradable drug delivery systems, in Proceedings of the 12th International Symposium on Controlled Release of Bioactive Materials (N. A. Peppas and R. J. Haluska, eds.). Controlled Release Society, Lincolnshire, IL, 1985, pp. 51-52. 

The design of biodegradable nano-hybrids has also been reported by Rhee et al. by the combination of a CaO-Si02 component with the biodegradable polymer, poly (epsilon-caprolactone) [30]. These nano-hybrids show hydroxyapatite-forming ability and are expected to show bioactivity and biodegradability. 

Preparation of a bioactive and degradable poly(epsilon-caprolactone) / silica hybrid through a sol-gel method. Biomaterials, 23, 4915-4921. 

Kamitakahara, M., Kawashita, M., Miyata, N., Kokubo, T. and Nakamura, T. (2004) Degradation of bioactive polydimethylxiloxane- CaO-SiOj-TiOj and poly(tetramethylene oxide)-CaO-Ti02 hybrids in a simulated body fluid. Journal of the American Ceramic Society, 87, 235-239. 

Although the biocompatibility and biodegradability of these materials were rapidly determined, the bioactivity of Si02-PCL hybrid materials was not studied until recently [99]. In order to provide bioactivity to Si02-PCL hybrid materials, Rhee prepared triethoxysilane end-capped poly(s-caprolactone) which was then cocondensed with tetraethyl orthosilicate and calcium nitrate via the sol-gel method. The Ca-containing PCL/silica hybrid so obtained showed in vitro bioactivity and biodegradability. The hybridization procedure between the a,co-hydroxyl PCL and silica phases was proposed to be as follows ... 

Sanchez-Chavez, M., Arranz, F. and Cortazar, M. (1998) Poly(vinyl alcohol) functionalized by monosuccinate groups. Coupling of bioactive amino compounds. Polymer, 39, 2751-2757. 

Rhee, S. and Choi J. (2002) Preparation of a bioactive poly(methyl methacrylate) /silica nanocomposite. Journal of the American Ceramic Society, 85, 1318-1320. 

Chen, Q Miyata, N. and Kokubo, T. (2003) Bioactivity and mechanical properties of poly (dimethylsiloxane) modified calcia-silica hybrids with added titania. Journal of the American Ceramic Society, 86, 806-810. 

Yoo, J.J. and Rhee S.H. (2004) Evaluations of bioactivity and mechanical properties of poly (e-caprolactone) silica nanocomposite following heat treatment. Journal of... 

Zhu J (2010) Bioactive modification of poly(ethylene glycol) hydrogels for tissue engineering. Biomaterials 31 4639-4656... 

In general, the main pollution problems associated with surfactants can be summarized as (1) foaming in river and wastewater treatment plants [314,326, 344,348,349,356,357], (2) transformation to bioactive metabolites (i.e., poly-ethoxylated alkylphenols, estrogenic compounds) under aerobic and anaerobic conditions [315,356], and (3) formation of certain cationics which are toxic to microorganisms at high concentrations [356,357]. 

Here we discuss dispersion polymerizations that are not related to vinyl monomers and radical polymerization. The first one is the ring-opening polymerization of e-caprolactone in dioxane-heptane (30). A graft copolymer, poly(dodecyl acrylate)-g-poly(e-caprolactone), is used as a stabilizer. The polymerization proceeds via anionic or pseudoanionic mechanism initiated by diethylaluminum ethoxide or other catalysts. The size of poly(caprolactone) particles depends on the composition of stabilizer, ranging from 0.5 to 5 i,m. Lactide was also polymerized in a similar way. Poly(caprolactone) and poly(lactide) particles with a narrow size distribution are expected to be applied as degradable carriers of drugs and bioactive compounds. 

An anesthetic drug, Richlocaine, developed jointly by scientists from Kazakhstan and Russia, and commercially available biologically active substances bovine serum albumin, lysozyme, and catalase were used. Hydrogels of acrylamide and acrylic acid copolymer(AA-AAc),poly(N-isopropylacrylamide)(PNIPA),N-isopropylacrylamide and acrylic acid copolymer (NlPA-AAc), N-isopropylacrylamide and 2-(acrylamido)-2-propanesulfonic acid copolymer (NIPA-APSA) were synthesized. Diffusion parameters of bioactive substances into hydrogel matrices were calculated using Eq. (19.1) ... 

Some of the most useful polyphosphazenes are fluoroalkoxy derivatives and amorphous copolymers (11.27) that are practicable as flame-retardant, hydrocarbon solvent- and oil-resistant elastomers, which have found aerospace and automotive applications. Polymers such as the amorphous comb polymer poly[bis(methoxyethoxyethoxy)phosphazene] (11.28) weakly coordinate Li " ions and are of substantial interest as components of polymeric electrolytes in battery technology. Polyphosphazenes are also of interest as biomedical materials and bioinert, bioactive, membrane-forming and bioerodable materials and hydrogels have been prepared. 

In an earlier investigation by the authors (1) biodegradable poly(ester-amides) were prepared and used as drug delivery devices for internally administered bioactive agents. Unsaturated analogs, (II), were prepared by Chu et al. (2). 

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