Page 6 - Clinical-Medical Solution for Clinical Chemistry

Application No.C123
News

Table 1 Results of Validation Test for Simultaneous Analysis of Antiepileptic Drugs
QC samples concentration
Range Accuracy (%) % RSD (n=6)
Compounds (ng/mL)
(ng/mL)
LLOQ Medium ULOQ LLOQ Medium ULOQ LLOQ Medium ULOQ
Levetiracetam 10 - 750 10 100 750 94.6 106.1 99.2 3.42 1.23 1.98
Felbamate 25 - 1000 25 250 1000 98.6 101.8 99.6 6.28 1.88 1.50
Topiramate 500 - 10000 500 2500 10000 102.3 97.1 100.6 6.71 3.58 2.96
Carbamazepine-10, 11-epoxide 5 - 1000 5 100 1000 92.9 107.8 99.3 7.48 3.32 1.41
Carbamazepine 10 - 1000 10 100 1000 90.6 110.3 99.1 3.79 3.42 1.19
Tiagabine 50 - 1000 50 250 1000 98.5 101.9 99.6 1.95 2.00 1.26
Diazepam 5 - 1000 5 250 1000 98.1 102.4 99.5 4.61 1.50 1.53

Table 2 Analytical Conditions for Antiepileptic Drugs
Column : Inertsil ODS-4 (50 mm L. × 2.1 mm I.D., 2 μm)
Mobile Phase : A 10 mmol/L Ammonium acetate - Water
: B Methanol
Flowrate : 0.4 mL/min
Time Program : B. Conc. 3 % (0 - 0.5 min) - 90 % (3.0 - 5.0 min) - 3 % (5.01 - 7.0 min)
Column Temperature : 40 °C
Injection Volume : 1 μL
Probe Voltage : 4.5 kV / - 3.5 kV (ESI-positive / negative mode)
DL Temperature : 150 °C
Block Heater Temperature : 400 °C
Nebulizing Gas Flow : 3 L/min
Drying Gas Flow : 10 L/min
MRM Transition : Levetiracetam (+) m/z 171.15 > 126.10, Felbamate (+) m/z 239.20 > 117.00,
Carbamazepine-10,11-epoxide (+) m/z 253.15 > 180.05,
Carbamazepine (+) m/z 237.20 > 194.05, Tiagabine (+) m/z 376.25 > 111.05,
Diazepam (+) m/z 285.15 > 153.95, Topiramate (-) m/z 338.10 > 78.00

n System Validation for Antiarrhythmic Drugs Analysis
TMD is used with a wide variety of drugs, and the properties, and in particular very different hydrophilic
physicochemical properties of these drugs differ properties.
individually. Therefore, confirming whether a given We chose the highly hydrophilic drug sotalol (partition
series of standard operations, which includes the coefficient: log P=2.6342) and the highly hydrophobic
process steps, tools, instruments and equipment used in drug amiodarone (log P=6.9326) and its active
an analytical workflow, are appropriate for the target metabolite N-desethylamiodarone were chosen, and
drug is important for ensuring the analytical results performed simultaneous analysis using the fully
obtained are valid. We introduce an example validation automated sample preparation LC/MS/MS system
of sample preparation and analysis operations using (Fig. 4).
antiarrhythmic drugs with very different physicochemical

(× 100,000)
Sotalol 273.10 > 133.00 (+)
5.0 AMD 646.00 > 58.20 (+)
DEA 618.00 > 72.20 (+)
Sotalol
NH
NH O
4.0 HO O S Amiodarone

I
O O N
3.0
N-Desethylamiodarone O I

I
2.0 O O NH
I
O
1.0

0.0

0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 min

Fig. 4 Mass Chromatogram of Three Antiarrhythmic Drugs and Drug Metabolite in a Control Serum Sample