Effect of different mobile phase ACN/MeOH compositions on the separation and chromatographic figures of merit for osmium Compound E on a 50 mm x 4.6 mm LARIHC CF6-RN column. Conditions; A; 100, MeOH, B: 80/20, MeOH/ACN, C: 60/40, MeOH/ACN, D: 40/60, MeOH/ACN, E: 30/70, MeOH/ACN. The mobile phases contained 0.2/0/3 ratio of FA/TEA additive, flow rate = 2.0 ml/min., detection λ = 280 nm.