Figure 3.

Chain length dependent effects of a homologous series of n-alkanols on the halothane induced quenching of RhoGDIα tryptophan emission fluorescence. A–F, the steady-state emission fluorescence intensity of RhoGDIα (500 nM) at 330 nm upon excitation at 295 nm was measured as a function of the concentration of n-alkanols with chain lengths, n=2 to n=7. The effects of the n-alkanols are expressed as the recovery in emission fluorescence from quenching by 0.2 mM halothane in the presence of each n-alkanol concentration. The solid curves represent fits of the data to Eq. 2 using least squares non-linear regression analysis. Calculated values of EC₅₀, h and F_max are listed in Table 1. Data are representative of three independent experiments. The fits of each individual replicate experiment yielded similar parameter values and errors. Other details are described in “Experimental Procedures.”