Bioactive polymer

Boccaccini AR, Erol M, Stark WJ, Mohn D, Hong Z, JoF Mano. Polymer/bioactive glass nanocomposites for biomedical applications a review. Compos Sci Technol 2010 70 1764-76. 

Department of Natural Polymers, Bioactive and Biocompatible Materials, Petru Poni Institute... 

Lu, H. H. EL-Amin, S. F. Scott, K. D. Laurencin, C. T. Three-dimensional, bioactive, biodegradable, polymer-bioactive glass composite... 

Figure 14.2 Elastic modulus versus compressive strength of biodegradable polymers, bioactive ceramics, and composites after [78]. Porosities of the porous scaffolds are >75% and mostly interconnected, (under permission)...

Developments in this field then became rapid due to those polymers bioactivity, and in the 1960s organotin polymers were reviewed Adrova et al. also described the incorporation of organotin moieties into the backbones of polymers using the strategy shown in Scheme 49. The reaction of monomer 194 with organotin hydrides such as 195 led to the isolation of polymer 196. This polymer had a degree of polymerization of approximately 25. 

Silane-polymer Bioactivity Delayed bone-like apatite growth several Zhang et al. (2004) and... 

Eig. 1. Schematic bioactive polyphosphazenes. (a) General stmcture, where X = hydrophilic /hydrophobic group that hydrolyzes with concurrent polymer breakdown, Y = difunctional group for attaching bioactive agent to polymer, and T = bioactive agent, (b) Actual example where X = —OC H, Y = and... 

C. G. Gebelein and C. E. Carraher, eds.. Biotechnology and Bioactive Polymers, Plenum Press, New York, 1994. 

Nowadays, a strategic area of research is the development of polymers based on carbohydrates due to the worldwide focus on sustainable materials. Since the necessary multi-step synthesis of carbohydrate-based polymers is not economical for the production of commodity plastics, functionalization of synthetic polymers by carbohydrates has become a current subject of research. This aims to prepare new bioactive and biocompatible polymers capable of exerting a temporary therapeutic function. The large variety of methods of anchoring carbohydrates onto polymers as well as the current and potential applications of the functionalized polymers has been discussed recently in a critical review [171]. Of importance is that such modification renders not only functionality but also biodegradability to the synthetic polymers. 

As mentioned in the introduction, various reviews over the last ten years show that many plants contain bioactive polysaccharides. Most of the plants studied were chosen due to their traditional use for different kinds of illnesses where the immune system could be involved. The following section will describe the pectic type polymers from the plants most studied for their structure, and activities related to the structure where possible. 

The first paper on the bioactive polysaccharides from Glycyrrhiza uralensis roots was published in 1996 by Kiyohara et al. [57]. They isolated a pectic type polymer with anti-complementary and mitogenic activity that was an acidic pectin, possibly containing rhamnogalacturonan type I as part of the total structure. Degradation of the uronic acid part of the molecule decreased both types of bio activities. The neutral oligosaccharide chains were shown to retain some of the activities of the native polymer, but it was suggested that they should be attached to the acidic core to retain maximum activity. 

Sufficient scientific data is still lacking to really pinpoint the bioactive sites of the pectic type polymers described in this chapter, but on the basis of the work of the group headed by Yamada over the last ten years, a better un-... 

From the science performed mainly over the last ten years it is obvious that the role of pectic substances in health care has been substantiated. For some of the pectic substances, parts of the structure of the bioactive sites have been determined, but further studies of the relevant structures for the individual active polymers must be performed in order to find a possible common structure for the activities observed. It also appears that there are special structural features present in some of the polymers, which are not foimd in others, and which are important for their activity, and this may explain the different behaviour of the polymers in the same system. 

Figure 9 from Paulsen BS (ed) Bioactive Carbohydrate Polymers. Yamada H (2000) Bioactive plant polysaccharides from Japanese and Chinese traditional herbal medicines , p 15-p24. Kluwer Academic Publishers, with permission from Springer. 

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