Achieving a broad dynamic range for any fluorometric or colorimetric method is a formidable challenge in chemistry and biology. For example, a commercial kit for hydrogen peroxide by fluorescence can be effective between 0.1 mM and 1 mM concentrations. Our method was quantitative in the 2-250 nM palladium concentration range. Therefore, if the palladium concentration in an API is expected to be above 250 ppm in the solid state, we recommend that the stock solutions of the sample be diluted to 0.1 mg/mL or lower. Comparison of the current method and our previous method revealed that the initial reaction rate is 54 times faster (i.e., the current method is 54 times more sensitive; Figure ).