Page 74 - Clinical-Medical Solution for Clinical Chemistry

Quantitative Multi Target Screening (MTS) using liquid
chromatography-tandem mass spectrometry with MS/MS library
based identi cation for forensic toxicology

MRM triggered product ion spectrum

MRM data was used to generate robust quantitation and also to help trigger product ion scans at three different
collision energies.

Compound ID Compound ID
Midazolam Diazepam
Molecular Formula Molecular Formula
C18H13ClFN3 C16H13ClN2O
CAS CAS
59467-70-8 439-14-5
285
Diazepam
Acquired Spectrum
CE 10V

291
Midazolam
Acquired Spectrum 223 249 Diazepam
CE 35V 209 Acquired Spectrum
CE 35V
129 187 258 326 193
154 205 222 241
0
163 189 265 326
129 244
Diazepam
Midazolam 209 Acquired Spectrum
Library Reference Spectrum 223 249 CE 55V
CE 35V
291 89
42 65 77 165 180 205
285
50 75 100 125 150 175 200 225 250 275 300 325 m/z
Diazepam
Merged Acquired Spectrum
CE 10-55V
193
42 65 77 165 180 205 222 241
0
65 77 91 165 180 206 222 241
154 193
Diazepam
Library Reference Spectrum
CE 10-55V
285

50 75 100 125 150 175 200 225 250 275 m/z

Figure 3. MRM triggered product ion spectrum data for midazolam and diazepam. The library included spectra for each collision energy and a separate
library for merged spectra enabling match criteria to be set for a speci c fragmentation voltage (as shown for midazolam) or to use a broad
band fragmentation and merged spectra (as in the case for diazepam).

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