Photobleaching comparison of fluorescein phalloidin and Alexa Fluor® 488 phalloidin.
Bovine pulmonary artery endothelial cells (BPAEC) were labeled with fluorescein phalloidin (left panels, Cat. no. F432), or Alexa Fluor® 488 phalloidin (right panels, Cat. no. A12379), which labels filamentous actin, and mounted in PBS. The cells were placed under constant illumination on the microscope with an FITC filter set using a 60× objective. Images were acquired at one-second intervals for 30 seconds. Under these illumination conditions, fluoresce in photobleached to about 20% of its initial value in 30 seconds; the fluorescence of Alexa Fluor® 488 phalloidin stayed at the initial value under the same illumination conditions.