Analysis of glucocorticosteroids by atmospheric pressure chemical ionization-liquid chromatography mass spectrometry (APCI-C/MS/MS)

Objective: To develop a rapid liquid chromatography / mass spectrometry / mass spectrometry (LC/MS/MS) method for testing of glucocorticosteroids, which are banned in sports by the World Anti-doping Agency from January 1^st 2004.
Materials and Methods : A total of 14 glucocorticosteroids were analyzed on LC/MS/MS using an Inertsil^® ODS-3 (3.0 µm, 50 mm ´ 4.6 mm i.d.) C-18 column in atmospheric pressure chemical ionization mode (positive ionization) with a mobile phase consisting of ammonium acetate and acetonitrile. The analytical equipment used was Aglient 1100 HPLC and API-3200 Triple quadrupole mass spectrometer.
Results : All glucocorticosteroids could be detected within 8 minutes. The limit of detection of all glucocorticosteroids by this screening method was 1 ng/ml. The recovery percentage at 25 and 50 ng/ml concentrations ranged from 54% (Prednisone) to 144% (Methylprednisolone).The validated method has been used successfully for testing of 500 in-competition samples. Excretion study samples of budesonide, methyl prednisolone and prednisone were analyzed by this method and the parent drugs as well as metabolites could be detected. However, further work is in progress to combine this procedure with another LC/MS/MS procedure in the ESI mode (positive ionization) being used for few anabolic steroids and heat-labile stimulants. This would help in screening of all corticosteroids, few anabolic agents and stimulants with just one injection, thus saving time and effort.

Keywords
Glucocorticosteroids, detection limit, liquid chromatography / mass spectrometry / mass spectrometry