Materials science combinatorial libraries

While considerable efforts have been spent in the past few years in the field of solid supports for combinatorial chemistry [73], most of them were devoted to modified polystyrenic beads with different sizes, loadings or swelling properties [74], or carrying different functionalities or linkers for library synthesis [75], or to solid supports different from resin beads (pins [76], cellulose [77], soluble supports [78], and so on). Few reports dealt with labelled solid supports prepared by chemical reactions (see the previous paragraphs) and significant efforts in the field of material sciences to obtain intrinsically labeled, nonchemically encoded, easily readable, combinatorial solid supports have not been reported. 

The enormous potential of this technique is evident from the above brief descriptions, which highlighted the many ideal properties of such encoding in terms of ease, reliability, inertness and robustness, automation, complete compatibility with any biological assay, and so on. No apparent drawbacks can be found, except maybe for the lack of expertise in this field by combinatorial and organic chemists and their reluctance in getting involved in material science. Examples of applications of these, or of similar approaches where the solid support is intrinsically and nonchemically encoded, to real large encoded organic molecule libraries should appear in the near future, and will hopefully increase the interest of the combinatorial community toward these techniques. 

Libraries composed of inorganic components, normally referred to as materials science libraries, surely represent one of the most intriguing and interesting class of combinatorial libraries. Since their recent appearance in combinatorial chemistry, they have been applied to many problems in the field of materials science, and an example is... 

In order to obtain combinatorial materials science libraries, sequential deposition must be coupled with a method to diversify the composition of small areas of the deposition surface. A moving-mask system, originally designed to obtain compositional gradients (20) and then used later for the synthesis of organic libraries (21), has been successfully and repeatedly used for this purpose. The first reported materials library LI (22) used this technique employing eight binary masks M0-M7, as shown in Fig. 11.2. 

Combinatorial chemistry is the production of libraries of compounds that represent permutations of a set of chemical or physical variables. In recent years, combinatorial chemistry has attracted considerable attention in materials science.11131 Originating from the discovery of new chugs by pharmaceutical companies, combinatorial methods have been employed in the areas of organic, biochemical, and inorganic chemistry, etc. In recent years, the combinatorial approach has been successfully applied to the hydro-thermal synthesis of zeolites and related materials.11141... 

Profile Founded in 1984, this privately held company provides molecular modeling and simulation software for both life and materials science research. The company employs more than 280 people (approximately half of whom are Ph.D. scientists) it operates sales offices around the world and a research and development facility in Cambridge, England. MSI s Combinatorial Chemistry Consortium addresses the full scope of the combinatorial chemistry process and is focused on maximizing the productivity of library design and analysis. In February 1998, Molecular Simulations Inc. and Pharmacopeia Inc. announced a definitive agreement whereby Pharmacopeia will acquire all of the outstanding stock of MSI. The transaction is expected to be completed in the second quarter of 1998 upon completion MSI will become a wholly owned subsidiary. 

Combinatorial chemistry is a synthesis strategy that enables the simultaneous production of large numbers of related compounds. These sets are referred to as libraries and they can be used in any discovery project associated with high-throughput analysis capabilities. The most common application is in drug discovery, but combinatorial methods also have been used, if less frequently, in the materials science area as well. 

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