Biotransformations in Supercritical Fluids

  • Nuno Fontes
  • M. Conceição Almeida
  • Susana Barreiros
Part of the Methods in Biotechnology book series (MIBT, volume 15)


A substance is said to be supercritical (SC) above a singular point on the phase diagram, the so-called critical point. The use of SC fluids as solvents for enzymatic transformations is a relatively new area of research (1,2) that is expected to expand in the future. Close to the critical point, small changes in temperature or pressure can effect large changes in the density/solvation ability of SC-fluid. This property of SC-fluids is currently used in a wide range of extraction applications. It can also be fruitfully exploited for the integration of biotransformation and downstream processing steps in a single bioreactor. In addition, lower viscosity and higher diffusivity of SC-fluids as compared to most organic solvents enable better mass transfer, which is often a limiting factor in reaction systems where the enzyme and reactants are not contained in the same phase.


Open Valve Close Valve Karl Fischer Titration Sapphire Window Good Mass Transfer 
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Copyright information

© Humana Press Inc. 2001

Authors and Affiliations

  • Nuno Fontes
    • 1
  • M. Conceição Almeida
    • 1
  • Susana Barreiros
    • 1
  1. 1.Universidade Nova de LisboaInstituto de Tecnologia Quimica e BiologicaOeirasPortugal

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