Enzyme catalysis steady-state kinetic treatment

Steady-state kinetic treatment of enzyme catalysis... 

Although free radical reactions are found less often in solution than in the gas phase, they do occur, and are generally handled by steady state methods. There are also organic and inorganic reactions that involve non-radical intermediates in steady state concentrations. These intermediates are often produced by an initial reversible reaction, or a set of reversible reactions. This can be compared with the pre-equilibria discussed in Section 8.4, where the intermediates are in equilibrium concentrations. The steady state treatment is also used extensively in acid-base catalysis and in enzyme kinetics. 

A reactant in an enzyme catalysed reaction is known as substrate. According to the mechanism of enzyme catalysis, the enzyme combines with the substrate to form a complex, as suggested by Henri (1903). He also suggested that this complex remains in equilibrium with the enzyme and the substrate. Later on in 1925, Briggs and Haldane showed that a steady state treatment could be easily applied to the kinetics of enzymes. Some photochemical reactions and some enzymic reactions are reactions of the zero order. 

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