FlAsH-EDT2是用于标记蛋白质的荧光探针。提出了荧光素砷发夹粘合剂（FlAsH）方法，用于荧光标记活细胞中的蛋白质。用膜渗透性荧光双砷染料荧光素砷发夹粘合剂-乙二硫醇（FlAsH-EDT2）标记蛋白质。可以通过廉价的前体染料荧光素和间苯二酚通过直接的两步程序以高收率制备可透过膜的荧光双砷化合物FlAsH-EDT2和ReAsH-EDT2。FlAsH-EDT2共价结合四半胱氨酸序列（CCPGCC）。 FlAsH-EDT2 is a fluorescence probe for labeling proteins. The Fluorescein Arsenical Hairpin Binder (FlAsH) method is presented for fluorescence labeling of proteins in living cells. Labeling proteins with the membrane-permeant fluorogenic biarsenical dye fluorescein arsenical hairpin binder-ethanedithiol (FlAsH-EDT2). The membrane-permeant fluorogenic biarsenicals FlAsH-EDT2 and ReAsH-EDT2 can be prepared in good yields by a straightforward two-step procedure from the inexpensive precursor dyes fluorescein and resorufin. FlAsH-EDT2 binds covalently to a tetracysteine sequence (CCPGCC).