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Nornicotine enantiomer resolution values and enantiomer distributions for selected tobacco extracts_ Separation conditions: 90/10% hexane/ethanol with 0_5% DEA – IB N-3 column flow 1 mL/min_, ambient temp_
| Nornicotine enantiomer values | Burley | Flue-cured | Oriental | VLN Tobacco |
|---|---|---|---|---|
| Average nornicotine enantiomer resolution, R | 2.86 | 2.26 | 2.97 | * |
| Average nornicotine R/S enantiomer ratio | 0.51 | 0.96 | 0.23 | * |
Variation in nornicotine enantiomers retention times (min) and resolution (R), as functions of EtOH modifier, modifier percentage, mobile phase flow rate, additive, additive structure, additive percent, and column type_
| IB N-3 column/mobile phase composition/flow rate | R | %RSD | RT*min | %RSD | RT*min | %RSD |
|---|---|---|---|---|---|---|
| 10% EtOH + 0.2% DEA, 0.8 mL/min | 2.8 | 2.8 | 14.4 | 2.4 | 13.2 | 2.4 |
| 10% EtOH + 0.5% DEA, 0.8 mL/min | 2.8 | 1.8 | 13.23 | 1.9 | 12.12 | 2.1 |
| 10% EtOH + 0.2% DEA, 1 mL/min | 2.9 | 4.6 | 13.3 | 0.6 | 12.1 | 0.6 |
| 10% EtOH + 0.5% DEA, 1 mL/min | 3 | 0.5 | 12.3 | 0.04 | 11.2 | 0.02 |
| 15% EtOH + 0.2% DEA, 0.8 mL/min | 2.3 | 1 | 10.9 | 0.8 | 10.1 | 0.9 |
| 15% EtOH + 0.5% DEA, 0.8 mL/min | 2.3 | 3.1 | 10.3 | 1.4 | 9.6 | 1.3 |
| 15% EtOH + 0.2% DEA, 1 mL/min | 2.1 | 0.9 | 8.6 | 1 | 8 | 0.9 |
| 15% EtOH + 0.5% DEA, 1 mL/min | 2.2 | 1.2 | 8.2 | 1.5 | 7.6 | 1.6 |
Influences on nornicotine and nicotine enantiomer retention times and resolution values (R) with systematic changes in mobile phase composition_
| Mobile phase | 85/15% Hex/EtOH with 0.5% DEA (v/v) | |
| Nicotine | Nornicotine | |
| Retention time (min) | 4.90 | 9.05 |
| Retention time (min) | 4.60 | 8.39 |
| R | 2.1 | 2.5 |
| Mobile phase | 90/10% Hex/EtOH with 0.5% DEA (v/v) | |
| Nicotine | Nornicotine | |
| Retention time (min) | 5.31 | 12.05 |
| Retention time (min) | 4.92 | 10.95 |
| R | 2.6 | 3.1 |
| Mobile phase | 98/2% Hex/EtOH with 0.5% DEA (v/v) | |
| Nicotine | Nornicotine | |
| Retention time (min) | 9.52 | 48.74 |
| Retention time (min) | 8.27 | 41.42 |
| R | 5.1 | 3.9 |