Biomaterials activation

Mechanisms of Leukocyte Adsorption. The exact mechanism of leukocyte adhesion to filter media is not yet fuUy understood. Multiple mechanisms simultaneously contribute to the adhesion of cells to biomaterials, however, physical and biological mechanisms have been distinguished. Physical mechanisms include barrier phenomenon, surface tension, and electrostatic charge biological mechanisms include cell activation and cell to cell binding. 

Gottenbosa B, Henny C, van der Meia, Klatterb F, Nieuwenhuisb P, and Busscher HJ. In vitro and in vivo antimicrobial activity of covalently coupled quaternary ammonium silane coatings on silicone rubber. Biomaterials, 2002, 23, 1417-1423. 

Presents current research activities on new rubbers, thermoplastic elastomers, nanocomposites, biomaterials, and smart polymers, as well as rubber blends, composites, and rubber ingredients... 

Abstract In this paper the synthesis, properties and applications of poly(organophos-phazenes) have been highlighted. Five different classes of macromolecules have been described, i.e. phosphazene fluoroelastomers, aryloxy-substituted polymeric flame-retardants, alkoxy-substituted phosphazene electric conductors, biomaterials and photo-inert and/or photo-active phosphazene derivatives. Perspectives of future developments in this field are briefly discussed. 

Understanding the relationship between molecular structure and materials piroperties or biological activity is one of the most important facets of biomaterials synthesis and new-drug design. This is especially true for polyphosphazenes, where the molecular structure and properties can be varied so widely by small modifications to the substitutive method of synthesis. 

In summary, preliminary results from two animal models (rabbit and mouse) indicate that poly(N-palmitoylhydroxyproline ester) elicits a very mild, local tissue response that compares favorably with the responses observed for established biomaterials such as medical grade stainless steel or poly(lactic acid)/poly(glycolic acid) implants. At this point, additional assays need to be performed to evaluate possible allergic responses, as well as systemic toxic effects, carcinogenic, teratogenic, or mutagenic activity, and adaptive responses. 

Upadhyay KK, Bhatt AN, Mishra AK, Dwarakanath BS, Jain S, Schatz C, Le Meins JE, Earooque A, Chandraiah G, Jain AK, Misra A, Lecommandoux S (2010) The intracellular drug delivery and anti tumor activity of doxorubicin loaded poly(y-benzyl L-glutamate)-b-hyaluronan polymersomes. Biomaterials 31(10) 2882... 

J Heller. Controlled release of biologically active compounds from bioerodible polymers. Biomaterials 1 51, 1980. 

The decreased denaturating action of the precursor and procedure enables one to immobilize reduced amounts of biomaterial. It was demonstrated in Ref. [55] that biocatalysts prepared by entrapping endo-l,3-P-D-glucanase and a-D-galactosidasc in amounts comparable to that in living cells had a reasonable level of activity. When the TEOS is applied, the enzyme content in silica matrix can be up to 20-30 wt.% to counterbalance losses due to denaturation [50]. 

Hench, L.L. and Wilson, J. (1984) Surface-active biomaterials. Science. 226, 630-636. 

Sakaguchi N, Kojima C, Harada A, Koiwai K, Kono K (2008) The correlation between fusion capability and transfection activity in hybrid complexes of lipoplexes and pH-sensitive liposomes. Biomaterials 29 4029 1036... 

Initially PDPs were synthesized by stepwise polycondensation of linear activated depsipeptide [93]. In 1985, Helder, Feijen and coworkers reported the synthesis of PDPs by ROP of a morpholine-2,5-dione derivative (cyclic dimer of ot-hydroxy- and a-amino acid cyclodepsipeptide, cDP) [94, 95]. The ROP method gives an alternative type of PDP by homopolymerization and also allows the copolymerization with other monomers (lactones and cyclic diesters) including LA, GA, and CL to give a wide variety of functional biodegradable materials. The synthesis of PDPs as functional biomaterials has been recently reviewed [17]. 

Arima Y, Toda M, Iwata H (2011) Surface plasmon resonance in monitoring of complement activation on biomaterials. Adv Drug Delivery Rev 63(12) 988-999... 

Toda M, Kitazawa T, Hirata I, Hirano Y, Iwata H (2008) Complement activation on surfaces carrying amino groups. Biomaterials 29 407 -17... 

Now with tissue engineering, regenerative medicine and combination products, active materials are the topic of interest of biomaterials specialists. 

Shaped activated carbons, 4 747 Shaped refractories, 6 491 Shaped-tube electrolytic machining (STEM), 9 599-600 Shape-memory alloys biomaterials, 3 741-750 Shape-memory alloys (SMAs), 22 339-354, 708t, 711-713, 721t applications of, 22 345-353 crystallography of, 22 341-345 ferrous, 22 342t future outlook for, 22 353 magnetically controlled, 22 712 nonferrous, 22 342t one-way, 22 712... 

The suitable materials for the above mentioned domains are polymers, metals and ceramics. Among these, polymers play an important role. Even the polymers have a lot of remarkable properties that could be used in biomaterials design, the interaction between these artificial materials and tissues and blood could create serious medical problems such as clot formation, activating of platelets, and occlusion of tubes for dialysis or vascular grafts. In the last few years, novel techniques of synthesis have been used to correlate desirable chemical, physical and biological properties of biomaterials. 

Kolhe, P, Khandare, J., Pillai, O., Kannan, S., Lieh-Lai, M., Kannan, R.M., Preparation, cellular transport, and activity of polyamidoamine-based dendritic nanodevices with a high drug payload. Biomaterials 27, 660-669 (2006). 

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