Operating Parameters for the LC/MS/MS Method for Measuring DEHP in the Lipid Test Extracts
| Operating Parameter | Operational Condition | ||||
|---|---|---|---|---|---|
| Column | Phenomenex Kinetex C18, 50 × 4.6 mm, 2.6 μ particle size | ||||
| Column Temperature | 30 °C | ||||
| Injection Size | 10 μL | ||||
| Mobile Phase A | 10 mM Ammonium acetate | ||||
| Mobile Phase B | 1/1 (v/v) Isopropyl alcohol/cyclohexane | ||||
| Mobile Phase C | Acetonitrile | ||||
| Mobile Phase D | 1/1 (v/v) Isopropyl alcohol/acetonitrile | ||||
| Mobile Phase Gradient | Time (min) | % A | % B | % C | % D |
| 0 | 30 | 0 | 70 | 0 | |
| 0.5 | 30 | 0 | 30 | 40 | |
| 5.0 | 1 | 0 | 99 | 0 | |
| 6.0 | 0 | 0 | 0 | 100 | |
| 12.5a | 0 | 100 | 0 | 0 | |
| 17.5a | 0 | 100 | 0 | 0 | |
| 18.0a | 0 | 0 | 0 | 100 | |
| 20.0a | 0 | 0 | 0 | 100 | |
| 21.0b | 30 | 0 | 70 | 0 | |
| Mobile Phase Flow Rate | 1.2 mL/min | ||||
| MS Operating Mode | APCI, + ion | ||||
| MS/MS Scan Segments | For DEHP, m/z = 413.4/301.2 amu | ||||