Abstract:
:Supercritical fluids are a unique class of nonaqueous media in which biocatalytic reactions can occur. The physical properties of supercritical fluids, which include gas-like diffusivities and liquid-like densities, can be predictably controlled with changing pressure. This paper describes how adjustment of pressure, with the subsequent predictable changes of the dielectric constant and Hildebrand solubility parameter for fluoroform, ethane, sulfur hexafluoride, and propane, can be used to manipulate the activity of lipase in the transesterification of methylmethacrylate with 2-ethyl-1-hexanol. Of particular interest is that the dielectric constant of supercritical fluoroform can be tuned from approximately 1 to 8, merely by increasing pressure from 850 to 4000 psi (from 5.9 to 28 MPa). The possibility now exists to predictably alter both the selectivity and the activity of a biocatalyst merely by changing pressure.
journal_name
Proc Natl Acad Sci U S Aauthors
Kamat SV,Iwaskewycz B,Beckman EJ,Russell AJdoi
10.1073/pnas.90.7.2940subject
Has Abstractpub_date
1993-04-01 00:00:00pages
2940-4issue
7eissn
0027-8424issn
1091-6490journal_volume
90pub_type
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