As can be observed in Table , there are several instances of data for logD that could not be computed since the logarithm of zero is undefined. This result is determined by the lowest concentration that could be detected on the HPLC instrument. Chromatography instruments are very precise and can calculate an analyte to a high degree of accuracy. However, there are limits of detection (LoD) based on the inherent molar absorptivity of the compounds and the dynamic range of the photo-diode array detector used to analyze the compounds. Additionally, the precision of the balances and pipettes that are used for sample preparation have a role in assessing the LoD. In the experiments presented here, it was determined that any chromatography data that presented an area below 5 milli-absorbance units (mAU), which equates to concentrations at or below 5 µg/mL, could not justifiably be provided.