HPLC method for quantification of arginine containing vasopressin

An isocratic technique was developed for the analysis of [Arg(8)]- vasopressin (AVP) by reverse-phase high performance liquid chromatography (RP-HPLC) using a 220 nm UV detection, Brownlee Spheri-5 ODS column (250 x 4.6 mm, 5 mu m, 100 Angstrom), mobile phase (methanol: 0.1% aqueous trifluoroacetic acid: : 3.7), and 1.5 mL/min flow rate. The coefficients of variation (C.V.) for precision and proportionality assays were lower than 2% for all concentrations studied. The detection limit, recovery rate, and tailing factor for AVP were 50 ng/mL (signal-to-noise ratio of 3:1), 0.97 +/- 0.03, and 0.99-1.1, respectively.