Under normal reading conditions, most plate readers take a single measurement in the center of each well. For non-homogeneous samples such as cell-based assays, where the cell distribution is uneven across the well, a single reading is inadequate. In some cases, a single center point reading may completely miss the material of interest in a large well format.
To overcome this problem, BMG LABTECH has equipped all of its readers with an advanced matrix scanning feature. During matrix scanning mode the microplate reader can take multiple measurements in each well with a resolution of up to 900 points/well (30 x 30 data point matrix). The software is able to display each scan point graphically and create a map for each well. The user can easily remove individual scan points or entire sections of each well map. The interface uses multiple color options to display data quickly in a number of different formats.
Combined with direct optic bottom reading, matrix scanning offers advanced cell-based analysis even in 384-well plates.
Orbital and Spiral Averaging
Another possible way to measure non-homogeneous well contents is BMG LABTECH's unique orbital and spiral averaging feature. Using these modes, the plate reader takes several measurements for each well on a defined orbit, collects the data and calculates an average. The following AppNote describes the use of well scanning for the evaluation of transfection efficiency using GFP and mcherry and highlights benefits of the individual options.