A β-D-glucuronic acid (GlcA) ligand equipped with a 5(6)-fluorescein reporter through a hydrophilic PEG3 spacer. The fluorescein label enables fluorescence detection, imaging, and binding readouts. This β-D-glucuronic acid (GlcA) probe carries a fluorescein reporter for fluorescence detection and imaging; GlcA is relevant to glucuronidation and glycosaminoglycan research and serves as a substrate for β-glucuronidase.