717019.fig.004a
(a)
717019.fig.004b
(b)
717019.fig.004c
(c)
Figure 4: (a) Effect of volume of FeCl3 for method B (1.5 μg mL−1 INH). (b) Effect of volume of ferricyanide for method B (1.5 μg mL−1 INH). (c) Reaction time and stability of colored species for method B (1.5 μg mL−1 INH).