A sensitive detection method for measuring both the free acid and ethyl amide forms of 17-phenyl trinor PGF_2α.

• Measure 17-phenyl trinor PGF_2α (also known as bimatoprost)
• Assay 24 samples in triplicate or 36 samples in duplicate
• Measure 17-phenyl trinor PGF_2α levels down to 2,6 pg/ml
• Colorimetric reading at 405 to 420 nm

17-phenyl trinor Prostaglandin F_2α (17-phenyl trinor PGF_2α) is a metabolically stable analog of PGF_2α and is a potent agonist for the FP receptor. It binds to the FP receptor on ovine luteal cells with a relative potency of 756% compared to that of PGF_2α. At the rat recombinant FP receptor expressed in CHO cells, 17-phenyl trinor PGF_2α inhibits PGF_2α binding with a KI value of 1,1 nM. In human and animal models of glaucoma, FP receptor agonist activity corresponds very closely with intraocular hypotensive activity. 17-phenyl trinor PGF_2α ethyl amide is an F-series prostaglandin analog which has been approved for use as an ocular hypotensive drug, sold under the Allergan trade name Bimatoprost. Whether 17-phenyl trinor PGF_2α ethyl amide is a prodrug analogous to prostaglandin ester prodrugs such as latanoprost is currently controversial. There is some evidence that unmetabolized 17-phenyl trinor PGF_2α is a weak FP receptor agonist. 17-phenyl trinor PGF_2α is converted by an amidase enzymatic activity in the bovine and human cornea to yield the corresponding free acid, with a conversion rate of about 40 µg/g corneal tissue/24 hours. Cayman’s 17-phenyl trinor PGF_2α ELISA is a sensitive detection method for measuring both the free acid and ethyl amide forms of 17-phenyl trinor PGF_2α. The assay is most appropriate for use when only one of the two forms is present. Samples containing mixtures of both the ethyl amide and free acid should be purified and the two compounds separated prior to ELISA analysis.