Page 73 - 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 quantitation

Area Ratio (x10) Area Ratio Area Ratio
Flurazepam Temazepam Diazepam
Quantitation MRM 3.0 Quantitation MRM Quantitation MRM
1.5 2.0
Rt 7.371 mins Rt 8.365 mins Rt 9.047mins
388.15>315.00 2.5 301.05>255.05 285.10>193.05
1.5
2.0
1.0
1.5
1.0
1.0
0.5 Linear regression analysis Linear regression analysis Linear regression analysis
R² = 0.9993 0.5 R² = 0.9999 0.5 R² = 0.9999
Matrix spiked calibration Matrix spiked calibration Matrix spiked calibration
0.0 0.0 0.0
0 250 500 0 250 500 0 250 500
Concentration (ug/L) Concentration (ug/L) Concentration (ug/L)

Mean Accuracy Repeatability
Calibration standards (n=3 for each calibration level) 20ug/L replicate (n=5) 100ug/L replicate (n=5)
Rt MRM
(mins) Mean Conc Mean Conc
5ug/L 20ug/L 100ug/L 500ug/L %RSD %RSD
(ug/L) (ug/L)
Flurazepam 7.371 388.15>315.00 109.5 95.5 95.3 101.1 18.1 3.0 100.2 7.7
Temazepam 8.365 301.05>255.05 103.4 97.8 99.1 100.2 18.8 1.9 101.5 6.0
Diazepam 9.047 285.10>193.05 102.0 99.5 98.6 100.3 18.6 2.5 100.2 5.6

Figure 2. Calibration curve data for urazepam, temazepam and diazepam spiked into whole blood and extracted using QuEChERS together
with results for accuracy and reproducibility at two different concentrations (20 µg/L and 100 µg/L; n=5; %RSD less than 8%).

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