Mimetic processing

In the future, porous catalytic MIP membranes could also serve as a key element for advanced integrated bio-mimetic processes in reaction engineering [112,113]. 

Calvert P. Bio-mimetic processing of ceramics and composites. In Uhlmaim DR, Ulrich DR, editors. Ultrastructure processing of advanced materials. New York Wiley 1992. p. 149-57. 

In this chapter, a novel interpretation of the membrane transport process elucidated based on a voltammetric concept and method is presented, and the important role of charge transfer reactions at aqueous-membrane interfaces in the membrane transport is emphasized [10,17,18]. Then, three respiration mimetic charge (ion or electron) transfer reactions observed by the present authors at the interface between an aqueous solution and an organic solution in the absence of any enzymes or proteins are introduced, and selective ion transfer reactions coupled with the electron transfer reactions are discussed [19-23]. The reaction processes of the charge transfer reactions and the energetic relations... 

Some non-silica sol-gel materials have also been developed to immobilize bioactive molecules for the construction of biosensors and to synthesize new catalysts for the functional devices. Liu et al. [33] proved that alumina sol-gel was a suitable matrix to improve the immobilization of tyrosinase for detection of trace phenols. Titania is another kind of non-silica material easily obtained from the sol-gel process [34, 35], Luckarift et al. [36] introduced a new method for enzyme immobilization in a bio-mimetic silica support. In this biosilicification process precipitation was catalyzed by the R5 peptide, the repeat unit of the silaffin, which was identified from the diatom Cylindrotheca fusiformis. During the enzyme immobilization in biosilicification the reaction mixture consisted of silicic acid (hydrolyzed tetramethyl orthosilicate) and R5 peptide and enzyme. In the process of precipitation the reaction enzyme was entrapped and nm-sized biosilica-immobilized spheres were formed. Carturan et al. [11] developed a biosil method for the encapsulation of plant and animal cells. 

It is clear that protein-carbohydrate interactions are essential in numerous biological processes and that the development of carbohydrate mimetics that interfere with these processes would provide a powerful methodology for both modulation and amelioration of specific biological activity. Since the early 1990s, novel... 

In the literature there are only few studies on the water-exchange processes of the manganese(II) species in general (33,38- 1), and the only seven-coordinate Mn(II) complexes studied are [Mn(EDTA) (H20)] and its derivatives (38,39,42,43). Such studies are essential for understanding the mechanism of the manganese-containing SOD mimetics. The volume of activation for the water-exchange reaction... 

It should be emphasized that virmaUy all of the above discussion is based on biomimetic chemistry, where the Fe(II) source varies from salts such FeS04 to the more reactive FeCla-THaO as well as heme mimetics (TPP) and ester hematin variants. When heme models are used, since porphyrin alkylation is a favoured process, end-product distributions of products can be very different from when a free ferrous ion source is employed. Furthermore, solvent has been shown to have a profound effect on the rate of reaction and product distributions obtained in iron-mediated endoperoxide degradation. Thus all of these studies are truly only approximate models of the actual events within the malaria parasites. Future work is needed to correlate the results of biomimetic chemistry with the actual situation within the parasite. In general, most workers do accept the role of carbon-centred radicals in mediating the antimalarial activity of the endoperoxides, but the key information defining (a) the chemical mechanism by which these species alkylate proteins and (b) the basis for the high parasite selectivity remains to be unequivocally established. 

Heparinoid polysaccharides such as heparan sul te and heparin are able to interact with numerous proteins and influence vital biological processes. Heparinoid mimetics were prepared to reduce the structural complexity of heparinoids and to obtain selectivities. This artide summarizes the development of heparinoid mimetics of different classes including representative syntheses and biological activities. Largely simplified compounds with regard to structure and synthetic access are described which maintain or exceed the activity of heparinoid polysaccharides. One of the recipes to increase binding or modify pharmacokinetic parameters was the introduction of hydrophobic groups. 

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