Biomaterial interfaces

Hench, L.L. and Paschall H.A. (1974) Histochemical responses at a biomaterials interface. Journal of Biomedical Materials Research Symposium, 5, 49. 

In addition, these thin films have been important in studies of electron transfer, relevant for catalytic systems [64], molecular recognition [65], biomaterial interfaces [66], cell growth [67], crystallization [68], adhesion [69], and many other aspects [70]. SAMs provide ideal model systems, because fine control of surface functional group concentration is possible by preparing mixed SAM systems of two or more compounds, evenly distributed over the surface [71, 72], as two- or... 

Meunier, A., Katz, J. L., Christel, P., and Sedel, L. (1988). A reflection scanning acoustic microscope for bone and bone-biomaterials interface studies. /. Orthopaedic Res. 6, 770-5. [197]... 

Redox enzymes are the active component in many electrochemical enzyme electrode biosensor devices.1821 The integration of two different redox enzymes with an electrode support, in which one of the biocatalysts is photoswitchable between ON and OFF states, can establish a composite multisensor array. The biomaterial interface that includes the photoswitchable enzyme in the OFF state electrochemi-cally transduces the sensing event of the substrate corresponding to the nonphoto-switchable enzyme. Photochemical activation of the light-active enzyme leads to the full electrochemical response, corresponding to the analysis of the substrates of the two enzymes. As a result, the processing of the signals transduced by the composite biomaterial interface in the presence of the two substrates permits the assay of the... 

Brunski, X B., Influence of biomechanical factors at the bone-biomaterial interface, in The Bone-Biomaterial Interface (X E. Davies, Ed.),pp. 391-404, University of Toronto Press, Toronto, 1991. 

Davies, J. E., The importance and measurement of surface charge species in cell behaviour at the biomaterial interface, in Surface Characterization of Biomaterials Progress in Biomedical Engineering, Volume 6 (B. D. Ratner, Ed.), pp. 219-234. Elsevier, New York, 1988. 

The authors thank the US Air Force European Office of Aerospace Research and Development, the Marie Curie Training Site for the Controlled Fabrication of Nanoscale Materials, and the Minerva Center for Microscale and Nanoscale Particles and Films as Tailored Biomaterial Interfaces for support of this work. 

Kasemo, B. and Lausmaa, J. (1991) in The Bone-Biomaterials Interface (ed. J.E. Davies), University of Toronto Press, pp. 19-32. 

As discussed in detail in Chapter 3.1, the advantage of bioinert materials is that they do not release any toxic constituents to the human body environment. However, on the downside they do not show positive interaction with living tissue. Instead, the body usually responds to these materials by forming a non-adherent fibrous capsule of connective tissue around the bioinert material that in the case of bone remodelling manifests itself by a shape-mediated contact osteogenesis. Consequently only compressive forces will be transmitted through the bone-biomaterial interfaces ( bony on-growth ). 

The aim of this paper is to present the use of a microwave digestor to prepare nanopowders via hydrothermal route. In the field of biomaterials the researchers (due to some problems with the traditional materials) are looking for the design of biomaterials with surface properties similar to physiological bone (grain sizes in the nanometric range [5]). This would aid in the formation of new bone at the tissue/biomaterial interface and therefore improve implant efficacy. With the advent of nanostructured materials (materials with grains sizes less than 100 nm in at least... 

Table VI. Important Material and Surface Properties at the Biomaterial Interface...

Figure 6. The primary interactions at a foreign biomaterial interface in the body are first with proteins and then with living cells. The drawing is schematic, and not to scale.

Blood responses. Blood is the fluid which transports body nutrients and waste products to and from the extravscular tissue and organs, and as such is a vital and special body tissue. The major response of blood to any foreign surface (which includes most extravascular surfaces of the body s own tissues) is first to deposit a layer of proteins and then, within seconds to minutes, a thrombus composed of blood cells and fibrin (a fibrous protein). The character of the thrombus will depend on the rate and pattern of blood flow in the vicinity. Thus, the design of the biomaterial system is particularly important for cardiovascular implants and devices. The thrombus may break off and flow downstream as an embolus and this can be a very dangerous event. In some cases the biomaterial interface may eventually "heal" and become covered with a "passive" layer of protein and/or cells. Growth of a continuous monolayer of endothelial cells onto this interface is the one most desirable end-point for a biomaterial in contact with blood. Figure 10 summarizes possible blood responses to polymeric biomaterials. 

Wong, J.Y., J.B. Leach, and X.Q. Brown, Balance of chemistry, topography, and mechanics at the cell-biomaterial interface issues and challenges for assessing the role of substrate mechanics on ceU response. Surf. Sci., 2004, 570 119-33. 

Figure 2 In wVo transition from blood-borne monocyte to biomaterial-adherent monocyte/macrophage to FBGC at the tissue-biomaterial interface. Little is known regarding the indicated biological responses, which are considered to play important roles in the transition to FBGC development.

The sequence of reactions which take place by the activation of the coagulation system at the blood/biomaterial interface are summarized in Fig. 3. The competitive adsorption behavior of proteins at the biomaterial surface determines the pathway and the extent of intrinsic coagulation and adhesion of platelets. Predictions about the interactions between the biomaterial surface and the adsorbed proteins can only be formulated by having an exact knowledge of the structure of the biomaterial s surface and the conformation of the adsorbed proteins. These interactions are determined both by the hydrophobic/hydrophilic, charged/uncharged, and polar/non-polar parts of the proteins and the nature of the polymer surface [25-27]. A commonly accepted fact is that decreasing sur-... 

The contact of biomaterial surfaces with the biological system blood provokes, with different intensity, activation of the intrinsic coagulation pathway at the blood/biomaterial interface. Clinically important and reproducible investigation methods are carried out to evaluate blood compatibility. The following coagulation parameters, obtained after the contact of the foreign surface with native, non-anticoagulant human whole blood in a modified Bowry blood chamber [93] and compared to the initial citrate plasma values, are evaluated ... 

Charalambides, P.G., Lund, J., Evans, A.G., McMeeking, R.M., 1989. A test specimen for determining the fracture resistance of biomaterial interfaces. J. Appl. Mech. 56, 77—82. 

Professor Criesser is Director of the Mawson Institute and has a longstanding international reputation particularly for his research on biomaterials Interfaces. He is a physical chemist by training and has applied this background to interdisciplinary research in various fields, particularly surface science, the analysis and modification of polymer surfaces, thin film deposition, biomaterials, and adhesion. 

The results of extensive corrosion testing, biocompatibility studies, and clinical evaluation have been used to select the corrosion-resistant metals and alloys that are in use as implants today. In addition, there are new materials being introduced as well as modifications of the currently used ones. Additional information on the biological and chemical reactions at the body/biomaterial interface would be useful in determining short- and long-term effects on the body and in pref>aring the biomaterial for its intended use. 

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