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Kromasil Eternity – Benefits
| Long-lasting columns | Control selectivity | Time efficiency | Scale up - scale down |
Long-lasting columns
We have performed long term stability tests under harsh pH conditions that show that Kromasil Eternity performs very well.
Amitriptyline
Prednisolone
Plate count evolution relative to initial value
| Columns: | Kromasil Eternity-5-C18 4.6 × 250 mm Waters XBridge, 5 μm, C18, 4.6 × 250 mm |
| Mobile Phase A: | 10 mM ammonium bicarbonate, pH 10.5/acetonitrile (90/10) |
| Mobile Phase B: | 10 mM ammonium bicarbonate, pH 10.5/acetonitrile (10/90) |
| Flow rate: | 1 ml/min |
| Temperature: | 45°C |
| Gradient: | 0 min 100% A, 0 min 100% B, 15 min 100% B, 16 min 100% A, 20 min 100% A |
| Test amitriptyline: | 10 mM ammonium bicarbonate pH 10.5/acetonitrile (30/70) |
| Test prednisolone: | 10 mM ammoniumbicarbonate pH 10.5/acetonitrile (70/30) |
| Test Cycle: | 6 × gradient + test = 172 min/cycle |
Control selectivity
Be free to choose the pH that will give you the best selectivity and optimal runtime for your application.
| Columns: | Kromasil Eternity-2.5-C18 4.6 × 50 mm |
| Mobile Phases: | acetonitrile/20 mM sodium phosphate pH 2.1, 7.2 and 11.0 respectively |
| Gradient: | 0-0.5 min: 10%, 5.5 min: 50% acetonitrile |
| Flow rate: | 1.5 ml/min |
| Temperature: | 25°C |
| Detection: | UV 254 nm |
Time efficiency
Smaller particles give higher plates count per meter. A shorter column with smaller particles can do the same work as a longer one with larger particles. Time and eluent consumption can be minimized.
run at 1/14 ot the original analysis
| Phase: | Kromasil Eternity-5-C18 | Phase: | Kromasil Eternity-2.5-C18 | Phase: | Kromasil Eternity-2.5-C18 |
| column size: | 4.6 × 250 mm | column size: | 4.6 × 100 mm | column size: | 4.6 × 50 mm |
| Flow rate: | 1.0 ml/min | Flow rate: | 1.6 ml/min | Flow rate: | 2.7 ml/min |
| Mobile Phase: | acetonitrile/water/formic acid (25/75/0.1) |
| Temperature: | 25°C |
| Detection: | UV 254 nm |
| Substances: | Mix of sulfa drugs, 1 = uracil, 2 = sulphathiazole, 3 = sulphamerazin, 4 = sulphamethoxazole |
Scale up - scale down
Scale-up your analytical application developed on small particles to a column with larger particles. Scale down your semi-prep purification step to a smaller column for efficient optimization. Retention times are maintained either way.
| Mobile Phase: | acetonitrile/50 mM triethylamine acetate, pH 11 (40/60) |
| Flow rate: | 0.43 ml/min and 9.0 ml/min for 4.6 and 21.2 mm i.d. columns, respectively |
| Temperature: | 20°C |
| Detection: | UV 230 nm |
| Sample: | Mix of β-blockers, 1 = uracil, 2 = atenolol, 3 = pindolol, 4 = metoprolol, 5 = propanolol, 6 = alprenolol |
