Determination of Methionine Hydroxy Analog MHA (CAS 583-91-5) on an ARION® Polar C18, 5 µm column (250 mm × 4.6 mm, ARI-5721-LM46). Isocratic elution with ACN : water (5:95 V/V) at 0.9 ml/min and 35 °C, UV detection at 215 nm. On the ARION® column the analyte is separated from the preceding matrix peak as a narrow band at about 9 minutes, while on the competitive column (competition G) it elutes earlier and broader, closer to the matrix. MHA® and Alimet® are trademarks registered by Novus International, Inc.