XFD555 phalloidin is a high-affinity F-actin probe conjugated to our bright, photostable, red-orange fluorescent XFD555 dye. XFD555, which is manufactured by AAT Bioquest, is structurally similar to Alexa Fluor™ 555 (Thermo Fisher).

Phalloidin, a bicyclic peptide toxin derived from Amanita phalloides (commonly known as the death cap mushroom), is widely recognized for its high-affinity and selective binding to filamentous actin (F-actin). Fluorescently conjugated phalloidin exhibits exceptional specificity for F-actin across a diverse range of species, including both plant and animal systems, with minimal nonspecific interactions. The conjugation of phalloidin to XFD555, a highly photostable and intensely fluorescent red-orange dye, offers an optimal combination of target specificity and fluorescence performance. This conjugate enables high-contrast, low-background imaging, facilitating precise visualization and quantification of F-actin structures in various biological applications.

XFD555 phalloidin can be used to visualize and quantitate F-actin in tissue sections, cell cultures, or cell-free preparations. XFD555 phalloidin staining is fully compatible with other fluorescent stains used in cellular analyses including fluorescent proteins, Qdots, and other iFluor® conjugates including secondary antibodies.