异硫氰酸荧光素（FITC）广泛用于通过胺基将荧光标记附着到蛋白质上。异硫氰酸酯基团与蛋白质中的氨基末端和伯胺反应。它已用于标记蛋白质，包括抗体和凝集素。 应用 荧光素异硫氰酸酯异构体 I已用于分生孢子的染色。 用于蛋白FITC标记的试剂；蛋白和肽的微测序（HPLC） Fluorescein isothiocyanate (FITC) is widely used to attach a fluorescent label to proteins via the amine group. The isothiocyanate group reacts with amino terminal and primary amines in proteins. It has been used for the labeling of proteins including antibodies and lectins.