Table 1.
Main mass spectrometry parameters for assaying ritonavir, lopinavir and efavirenz
| Parameter | Ritonavir | Lopinavir | Ritonavir-d6 (IS)* | Efavirenz | Celecoxib (IS)** |
|---|---|---|---|---|---|
| Declustering potential (DP), V | 26 | 76 | 60 | −75 | −125 |
| Entrance potential (EP), V | 10 | 10 | 10 | −10 | −10 |
| Collision energy (CE), eV | 91 | 25 | 40 | −52 | −52 |
| Collision cell exit potential (CXP), V | 8 | 15 | 15 | −5 | −5 |
| CAD gas, psi | 7 | 7 | 7 | 6 | 6 |
| Curtain gas, psi | 10 | 10 | 10 | 14 | 14 |
| GS1, psi | 50 | 50 | 50 | 30 | 30 |
| GS2, psi | 50 | 50 | 50 | 30 | 30 |
| Ion spray voltage, V | 5500 | 5500 | 5500 | −4500 | −4500 |
| Probe temperature, °C | 600 | 600 | 600 | 400 | 400 |
| Q1>Q3, m/z | 721.3>140.1 | 629.3>447.1 | 727.2>302.2 | 314.2>69.0 | 379.9>68.9 |
| Dwell, ms | 150 | 150 | 150 | 200 | 200 |
*
Ritonavir-d6 was used as IS for ritoanavir and lopinavir.
**
Celecoxib was used as IS for efavirenz.