Liquid Chromatography-Mass Spectrometry for the Determination of Antidepressants and Some of their Major Metabolites in Human Biological Matrices - LC-MS in Drug Bioanalysis - page 165

Table 2 MRM transitions, cone voltages (CV), and collision energies (CE) used in the analysis of
the antidepressants and the deuterated internal standards included in the LC-MS/MS method
Compound CV Transition CE

Venlafaxine 25 278.1 > 57.8

278.1 > 260.3

18
12

Citalopram 35 325.1 > 109.1

325.1 > 262.1

26
20

Desipramine 25 267.0 > 43.8

267.0 > 71.8

40
15

Imipramine 25 281.1 > 57.6

281.1 > 85.9

40
16

Paroxetine 35 330.0 > 69.7

330.0 > 192.3

30
20

Nortriptyline 25 264.2 > 90.8

264.2 > 233.3

22
16

Fluvoxamine 25 319.0 > 70.8

319.0 > 86.8

18
18

Amitriptyline 30 278.1 > 90.8

278.1 > 233.2

24
18

Nor fl uoxetine 15 296.0 > 29.8

296.0 > 134.1

10
6

Sertraline 18 306.0 > 159.1

306.0 > 275.1

26
12

Fluoxetine 22 310.1 > 43.7

310.1 > 148.2

12
8

Norclomipramine 25 301.1 > 71.8

301.1 > 270.2

18
16

Clomipramine 32

20
Imipramine-3 25 284.1 > 89.0 15
Paroxetine-d6 35 336.1 > 76.0 30
Nortriptyline-d3 30 267.1 > 233.3 15
Nor fl uoxetine-d6 15 302.2 > 140.1 6
Fluoxetine-d6 25 316.1 > 43.7 12
Clomipramine-d3 30 318.1 > 88.9 18
Underlined transitions were used as quantifiers ( Source : From de Castro A et al. (2008) J Pharm
Biomed Anal. 48:183. With permission)

22 315.0 > 57.8

315.0 > 85.9

6.3.2 Calibration Model

Calibration curves ( n = 6, six different days) were generated at eight concentration
levels in the range from 2 to 500 ng/mL and 2-1,000 ng/mL for oral fluid and
plasma, respectively. Coefficient of determination ( r 2 ) was >0.99 for all analytes
using a 1/ x weighted linear regression, except for fluvoxamine, for which a
quadratic response was observed.