This application note describes a method for impurity profiling using capillary electrophoresis (CE) and ion trap mass spectrometry (IT).
The document details an analytical method for monitoring drugs, drug impurities, and metabolites using Capillary Electrophoresis (CE) coupled with Ion Trap Mass Spectrometry. It highlights that CE offers greater resolution and selectivity compared to HPLC, particularly for polar Phase II metabolites.
The study utilizes the Agilent 1100 Series LC/MSD Trap ion trap mass spectrometer coupled with an Agilent 1100 Series CE system. The method employs clenbuterol and isoproterenol as model compounds to demonstrate the capability of generating characteristic impurity fingerprints using automated, data-dependent MS/MS acquisition.
| Buffer composition | 20 mM ammonium formate, pH 3.2 |
|---|---|
| Capillary dimensions | 80 cm (20 cm to UV) x 50 µm id. |
| Injection volume | 6 µl |
| Sheath flow rate | 6 µl/min |
| Ionization mode | Positive ESI |
| Drying gas flow | 10.0 l/min |
| Nebulizer pressure | 10 psig |
| Scan range | 50-500 m/z |
Clenbuterol and isoproterenol were used as model compounds because of their similar chemical structures and properties.
The dynamic range allows the detection and confirmation of impurities at least at the 0.1% level (w/w) of the main compound.
Capillary electrophoresis offers greater resolution and a different selectivity when compared to reversed-phase HPLC.