Achieving optimal mixing results, especially in all the various 384-well formats, can be an elusive goal. Artel developed a quantitative method that allows for the testing of a mixer or mixing protocol by using dual-dye photometry. To test for optimal mixing, two solutions are dispensed into a microtiter plate, which is then subjected to a predetermined mixing program. A premixed control consisting of the two solutions is used to account for potential non-mixing related factors. The average absorbance, standard deviation, and coefficient of variation (CV) of each solution, computed over multiple mixing trials, provide data regarding the efficiency of the mixer and protocol.
In an effort to find a mixing device that optimally mixed in 384-well microtiter plates, we evaluated the TechElan TEOS 150 orbital mixer. The dual-dye method was used to test the mixing capabilities of the TEOS 150 for optimal mixing in a 384-well microtiter plate. As discovered via the dual-day method, the type of microtiter plate tested possessed characteristics which created a difficult mixing scenario. However, through a collaborative effort between Artel and TechElan, the data analyses lead to modifications of the TEOS 150, which endured optimal mixing in the 384-well microtiter plate.