Determining Dilution Accuracy in Microtiter Plate Assays Using a Quantitative Dual-Wavelength Absorbance Method

Dilution-based volume transfer steps are commonly performed for many types of microtiter plate-based assays. Because the exact concentrations of target samples in solution are typically not directly measured but calculated from the dilution ratio, it is important to accurately measure each dilution step so that the ultimate concentrations of those samples can be known. This paper describes a new approach, which is based on dual-dye, dual-wavelength photometry, for accurately measuring each dilution step in a multistep dilution protocol. The theory behind this method is described, as well as an experimental demonstration of the prescribed approach.