Biological methods future developments

Conjunction of the chromatographic methods of component separation with methods of analysis of biological properties provides great opportunities in their analysis. This has made the search for bioactive substances easier and will aid the future development of new research methods. 

The lipase-catalysed access to enantiomerically pure compounds remains a versatile method for the separation of enantiomers. The selected examples shown in this survey demonstrate the broad applicability of lipases in terms of substrate structures and enantioselectivity. More recently, modem molecular biology methods such as rational protein design and especially directed evolution103 will further boost the development of tailor-made lipases for future applications in the synthesis of optically pure compounds. It has been already shown that a virtually non-enantioselective lipase (E=l.l in the resolution of 2-methyldecanoate) could be evolved to become an effective biocatalyst (E>50). Furthermore, variants were identified which showed opposite enantiopreference. 

In fact, of all the methods surveyed, NMR is the most versatile and powerful (although not the most sensitive). If future developments bring about major improvements in its sensitivity, NMR microscopy, in which NMR spectra of different compartments in a biological specimen can be recorded in vivo, could provide a new oudook on the determination of metal speciation in natural systems. 

The biological methods class of reagents holds the most promise for rapid development in the near future because most reactions are asymmetric. The problems that are being overcome are the tight substrate specificity of many enzymes and the need for co-factor regeneration. Systems are now being developed for asymmetric synthesis rather than resolution approaches. Some of these reactions are discussed in Chapters 19 through 21, but see also Chapters 2 and 3. 

The intention is not to comprehensively review the literature that describes the multidisciplinary efforts of researchers to create interfacial supramolecular assemblies. The literature in this area is vast and involves research programs in chemistry, physics and biology, as well as analytical, materials and surface sciences. Rather, key examples of advances that have significantly influenced the field and will direct its future development are presented. In addition, some of the analytical methods, theoretical treatments and synthetic tools, which are being applied in the area of interfacial supramolecular chemistry and are driving its rapid development, will be highlighted. 

Despite the reservations noted above, it would be improper if no comment at all were made on the future of new techniques. In general, the trends of the last few decades suggest that developments in spectroscopy, chromatography and biological methods will continue to take place. Some of these will be in the direction of improving the speed, sensitivity and resolution of existing techniques, others may be the establishment of entirely new methods. 

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