Column used | Mobile phase | Flow rate | Wave length | Observation | Result |
---|---|---|---|---|---|
Microbondapak C18, 5 μm, 50 × 4.6 mm i.d. | Methanol only | 0.5 ml/min | 254 nm | Low resolution below 1. | Method rejected |
Phenomenex RP- C18, Luna 5 μm, 250 × 4.6 mm i.d. | Acetonitrile only | 0.8 ml/min | 358 nm | Resolution i.e. 1.2 but not satisfied | Method rejected |
Microbondapak C18, 5 μm, 50 × 4.6 mm i.d. | Acetonitrile: phosphate buffer(pH7.8) = 70:30 | 1 ml/min | 270 nm | Poor resolution i.e. 1.5 | Method rejected |
Phenomenex RP- C18, Luna 5 μm, 250 × 4.6 mm i.d. | Acetronitrile: phosphate buffer(pH 5.0 = 60:40 | 1 ml/min | 270 nm | Poor resolution i.e. 1.2 | Method rejected |
Develosil ODS HG-5 RP C18, 5 μm, 15cm × 4.6 mm i.d. | Acetonitrile: phosphate buffer(pH 3.4) (60:40) | 1 ml/min | 268 nm | Sharp peak and good resolution i.e. 2.3 | Method accepted |