Page 5 - Clinical-Medical Solution for Clinical Chemistry

Application No.C123
News

Fig. 2 shows the mass chromatogram for a control mass and structure of those drugs, the results show no
sample consisting of seven antiepileptic drugs and drug apparent interference from other constituents in the
metabolites added to human blood serum. Because LC/ blood serum.
MS/MS can detect target drugs selectively based on the

(× 100,000)
2.00 Levetiracetam 171.15 > 126.10 (+)
Felbamate 239.20 > 117.00 (+)
Topiramate 338.10 > 78.00 (-) Levetiracetam
Carbamazepine 10-11-epoxide 253.15 > 180.05 (+)
Carbamazepine 237.20 > 194.05 (+)
Tiagabine 376.25 > 111.05 (+) Felbamate
Diazepam 285.15 > 153.95 (+)
Topiramate
1.50
Carbamazepine 10-11-epoxide
Carbamazepine
1.00 Tiagabine

Diazepam
0.50

0.00
2.00 2.50 3.00 3.50 4.00 4.50 min

Fig. 2 Mass Chromatogram of Seven Antiepileptic Drugs and Drug Metabolites in a Control Serum Sample

Calibration curves were prepared by continuous analysis accuracy within 100 % ±15 % over the entire
with fully automated sample preparation and analysis, measurement range including the minimum limit of
and used to assess accuracy and precision (repeatability). quantification. Similarly, precision was measured at a
Good linearity was obtained across the set calibration %RSD of within 15 %, showing that good repeatability
curve range for each antiepileptic drug (Fig. 3), with was achieved (Table 1).

Area Area Area
2250000 175000
2000000 Levetiracetam 500000 Felbamate Topiramate
150000
1750000 400000
1500000 125000
1250000 300000 100000
1000000 75000
200000
750000
50000
500000 2 100000 2 2
=
250000 r = 0.999 r 0 9 . 9 9 25000 r =0.999
0 0 0
0 250 500 750 Concentration 0 250 500 750 Concentration 0 2500 5000 7500 Concentration
Area Area Area
3000000
Carbamazepine 5000000 Carbamazepine 1500000 Tiagabine
2500000 -10,11-epoxide 4000000 1250000
2000000
3000000 1000000
1500000
750000
2000000
1000000
500000
2
=
2
500000 r 2 = 0.999 1000000 r 0 9 . 9 9 250000 r =0.999
0 0 0
0 250 500 750 Concentration 0 250 500 750 Concentration 0 250 500 750 Concentration
Area
700000
Diazepam
600000
500000
400000
300000
200000
2
100000 r =0.999
0
0 250 500 750 Concentration
Fig. 3 Calibration Curves of Seven Antiepileptic Drugs and Drug Metabolites