Fig. 1

Comparison of the efficiency of calcein versus Alizarin Red to detect mineralized areas of osteoblast culture. a mineralization pattern detected by Olympus IX2-UCB Fluorescent microscope, phase-contrast (left panel, calcium hydroxyapatite deposits appear like yellowish structures at phase-contrast); the same section on the plate visualized by calcein by fluorescent setting (middle panel); overlap between the phase-contrast and fluorescent images in composite setting (right panel), scale bars 2000 μm. Representative pictures are shown, n = 3. b Calcein staining and Alizarin Red staining of the same mineralized areas detected by IncuCyte ZOOM: note that the phase-contrast objective of the IncuCyte ZOOM does not show the red color of Alizarin Red, however the pattern of the staining is clearly visible in gray scale and can be compared to the calceinpattern; representative pictures are shown, n = 3