The paper introduces the application of LC/MS in drug monitoring, which can be used to analyze over 200 drugs, including identification and quantification.
The document presents a method for Therapeutic Drug Monitoring (TDM) of clozapine and its metabolite, desmethylclozapine, performed at St. Olav Hospital using the Agilent 1100 LC/MSD system. It highlights the advantages of this technique over immunoassays for analyzing drugs with narrow therapeutic indices and discusses interindividual variability in drug response.
The text provides specific details on the experimental procedure, including a step-by-step extraction protocol for blood serum and the instrumental conditions required for Liquid Chromatography/Mass Spectrometry (LC/MS) analysis. It also reports on the system's performance through reproducibility data derived from quality control samples over three months.
| Column | ZORBAX SB-C18, 4.6 mm x 30 mm x 3.5 pm |
|---|---|
| Mobile phase | Methanol: 50-mM ammonium acetate in water (60:40) |
| Flow rate | 1 mL/min |
| Injection Volume | 2.5 pL |
| Nebulizer pressure and temperature | 25 psi at 350 °C |
| Drying gas flow rate | 9 L/min |
The analysis is performed using the Agilent Technologies 1100 LC/MSD.
Typical serum levels for patients range from 450 nM to 3000 nM.