physics and chemistry basis of biotechnology - de cuyper & bulte

[...]... reproduced from generation 9 M De Cuyper and J.W.M Bulte (eds.), Physics and Chemistry Basis of Biotechnology, 9–45 © 2001 Kluwer Academic Publishers Printed in the Netherlands Aleksey Nedoluzhko and Trevor Douglas to generation The control exerted in the formation of these biominerals has captured the attention of materials scientists because of the degree of hierarchical order, from the nanometer to the meter... demineralised protein (apoferritin) provides a spatially constrained reaction environment for the formation of inorganic particles which are rendered stable to aggregation Ferritin is able to withstand quite extreme conditions of pH (4. 0-9 .0) and temperature (up to 85°C) for limited periods of time and this has been used to advantage in the novel synthesis and entrapment of non-native minerals Oxides... initiate mineralization of iron oxyhydroxides, CdS, PbS and silica (Figure 3) These materials form as thin coatings at the protein solution interface through processes such as oxidative hydrolysis, sol-gel condensation and socrystallisation and result in formation of mineral fibres, having diameters in the 2 0-3 0 nm range In addition, there is evidence for ordered end-to-end assembly of individual TMV particles... synthesis of silver metal particles was demonstrated using the same general approach Although the average particle size was clearly dependent on w (from 30 Å (w = 5) to 70 Å, (w = 15)) the size distribution was rather broad (s= 30 - 40 %) Chang et a1 [50] demonstrated synthesis of silica particles by the hydrolysis of tetraethoxysilane in water-in-oil microemulsions in the presence of ammonium hydroxide and. .. SYNTHESIS ALEKSEY NEDOLUZHKO AND TREVOR DOUGLAS Department of Chemistry, Temple University Philadelphia, PA 1912 2-2 585 USA Abstract The study of mineral formation in biological systems, biomineralisation, provides inspiration for novel approaches to the synthesis of new materials Biomineralisation relies on extensive organic-inorganic interactions to induce and control the synthesis of inorganic solids Living... synthesis 3.2 SYNTHETIC POLYAMIDES - DENDRIMERS Some interesting synthetic polypeptides are emerging in the field of materials chemistry, in particular dendritic polymers based on poly(amidoamine) or PAMAM dendrimers These polymers are protein mimics in that they too are polyamides, have fairly well defined structural characteristics (topology), and can accommodate a variety of surface functional groups... depending on the film type Exposure of the film to light forms a "latent image" (a small critical nucleus of silver metal) that will catalyse the reduction (and growth of a silver crystal) of that particular grain when the film is developed The development process is the chemical reduction of the silver halide grains and the growth, in its place, of a microcrystal of silver metal The matrix serves to... process and to create synthetic bone-like material Matrix proteins isolated from bivalves have been shown to mediate nucleation and growth of calcium carbonate [3 5-3 8] These materials are composites of microscopic crystals held together by a protein "glue" and have the advantages of both the hardness of the inorganic material, and the flexibility of the organic matrix Composite materials such as these often... (water-in-oil microemulsions) General principles for the synthesis of inorganic materials in these environments involve dissolution of reactants in the aqueous phase and the subsequent reactions, which occur due to micelle collisions, accompanied by the exchange of their aqueous phases Figure 6 The dependence of particle size on water-to-surfactant ratio CdS (triangles), PbS [squares), CdyZn1-yS [circles),... perchlorate and sodium sulphide The increase of particle size with water-tosurfactant ratio w was reported This dependence was shown to occur only at w < 15, with the particle size being almost constant at higher w values [43] (Figure 6) Maximum particle size was reported to be twice that of CdS particles prepared with a two-fold excess of S 2-, than for those prepared in a two-fold excess of Cd2+ Figure . conditions of pH (4.0 - 9.0) and temperature (up to 85°C) for limited periods of time and this has been used to advantage in the novel synthesis and entrapment of non - native minerals. Oxides of Fe(II/III). Belgium and J. Chabert, Minister for Economy of the Brussels Capital Region. Physics and Chemistry Basis of Biotechnology Volume 7 Edited by MARCEL DE CUYPER Katholieke Universiteit Leuven,. choice of material and morphology to suit a particular function. In addition, the overall material is often faithfully reproduced from generation 9 M. De Cuyper and J.W.M. Bulte (eds.), Physics and