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HPLC Application Sheet
Steriods Mixture (3) - Cogent UDC-Cholesterol™
Method Conditions
| Mobile Phase |
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| |
Chromatogram A: |
60% Aqueous (0.1%TFA)
40% Acetonitrile (ACN) |
| Chromatogram B: |
45% Aqueous (0.1%TFA)
55% MeOH |
| Chromatogram C: |
56% Aqueous (0.1%TFA)
24% MeOH and 20% ACN |
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| Column |
Cogent UDC-Cholesterol™ |
| Catalog No. |
69069-75R |
| Dimensions |
75 x 4.6mm id |
| Flow Rate |
1.0ml/min |
| Detection |
UV, 240nm |
| Temperature |
15°C |
Discussion of Chromatograms
An FDA requirement for Birth Control Product Analysis is the resolution of hormonal steroids ETES and ESTN.
- With Cogent Bidentate C18™ and Cogent UDC-Cholesterol™ HPLC columns, peaks ETES and ESTN are resolved with
polarity-based, Reverse Phase, ACN as the organic modifier.
- With other C18 columns, these same peaks are not resolved.
- When eluting with the shape recognition in Methanol on the Cogent UDC Cholesterol™ column, ETES and ESTN are
extremely well resolved. However, in this test mix ETES now co-elutes with ESTD.
- By mixing the selectivity mechanisms, polarity (ACN) and shape recognition (MeOH), partial resolution was achieved on
all compounds using the UDC Cholesterol™ column. Scaling up to a 250x4.6mm column resulted in baseline resolution of
all peaks.
Implications, Advantages & Uses
Using a single UDC Cholesterol™ column with orthogonal selectivity, polarity in ACN and shape recognition in
Methanol can lead to unique problem solving.
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