Gamma-Guanidinobutyric acid (4-GBA) is used to study intestinal transport by the human proton-coupled amino acid transporter(s) (hPAT1). 4-GBA is used with other model compounds such as 1,6-diaminohexane, 1,6-diguanidinohexane, and 1,6-di(cyanoguanidino)hexane to study the biodegradability of the biocide polyhexamethylene biguanide (PHMB).
