COXCEXTKATION-TIME CURVES FOR INHIBITION 



599 



(I) OR [(I)-(I)J 



100 



Fig. 12-41. Logarithmic plots of Eq. 12-89. In curve A, t 



is plotted again.st (I), and in curve B, (t — f,„) is plotted 



against [(I) — (!)„]. (I),„ = 3, t„ = 2, and C = 10. 



The marked differences in the rates of inhibition and the potencies of these 

 compounds are well illu-strated by these constants in an equation of the 

 type [(I) — (I)„J"^ == C. It was shown that the delay in the killing action 

 was not due to fixation of the substances, since this was relatively rapid, 

 but to intracellular processes, probably including the time required for 

 the arsenical to react with the susceptible enzymes and the subsequent pro- 

 cesses leading to the death of the cells. 



Interpretation of Concentration-Time Curves 



There is no question but that concentration-time curves allow kinetic 

 data to be presented in a compact and useful form and that the fitting of 



