Microwave chemistry has an edge over conventional heating methods for conducting chemical reactions, and it will soon emerge as the preferred technology for performing chemical synthesis relating to lead development in pharmaceutical and biotechnology companies. Moreover, the use of microwave chemistry for industrial production holds promise, since research has already been initiated to scale up microwave chemistry reactions from milligrams to kilograms.
Over the past three decades, microwave chemistry has evolved as an established field of science, due to intensified research in the area. In the future, microwave chemistry is likely to become a preferred method for conducting analytical and synthetic reactions in laboratories. This is validated by the increasing number of publications in the field, from about 500 in 1997, to over 2000 up to 2004. At present, about 25,000-30,000 chemists use microwave technology to conduct chemical reactions worldwide.
Initially, microwave chemistry was primarily used to carry out analytical processes such as ashing, digestion, extraction, fat analysis and protein hydrolysis. As microwave chemical synthesis has advanced, its applications have been extended to include the synthesis of fine chemicals, organometallic, coordination, intercalation compounds, and nanoparticles. Microwave technology also enables chemists to achieve cleaner and more efficient chemical reactions with higher yields, compared to conventional heating methods.
The microwave chemistry equipment market was estimated to be $ 89m in 2003. Although the market size is relatively small at present, in view of current growth trends, it is expected to reach $145.8m by 2008. This growth will be driven by advancement in equipment technology and growing awareness of technology, its success, and the advantages.
The equipment market is divided into two parts, i.e., chemical analytics and chemical synthesis. Though the analytical segment currently holds a larger share of the market, this may change in the future, since the chemical synthesis segment is expected to grow at a much faster rate. The key players in the microwave chemistry market are CEM Corporation, Biotage AB and Milestone s.r.l, with CEM Corporation holding the largest market share.
Two categories of equipment used in microwave chemistry, based on design requirements: single-mode and multi-mode microwave ovens. Both types cater to a specific market segment. Single-mode microwave equipment is primarily used for chemical synthesis, whereas multi-mode microwave equipment is mainly used for chemical analysis.
This equipment has been limited to laboratories due to lack of scalability of the technology. Presently, the manufacturers are directing their research to develop products that can increase the yield volume substantially. These new products have been successful in augmenting the scale of reactions from the level of 0.2 mL to 500 mL. However, scalability to the level of industrial production has still not been achieved, which questions the commercial viability of microwave chemistry.
In addition, there is a demand for a further increase in the rate of reaction. Consequently, instrument manufacturers are developing prototypes that will be able to achieve high-pressure conditions inside the reaction vessel, resulting in an increased rate of reaction. Other areas of research include design modifications in the existing equipment, to provide safer reaction conditions; and development of equipment that can be used for chemical analysis as well as chemical synthesis.
In light of the limited research that has taken place in microwave chemistry till date, it offers researchers enormous scope for research and development. This is evident from the small number of patent publications (94) granted in this field over the past 30 years of research. Of these, about 68 were granted in the area of chemical analysis in the last two decades, and 48 in the field of chemical synthesis in the last six years. This indicates that the focus of research and development in microwave chemistry is shifting from chemical analysis to chemical synthesis.