Simultaneous quantification and qualification of synacthen in plasma

• Published in: Analytical and bioanalytical chemistry Vol. 399; no. 5; pp. 1835 - 1843
• Main Authors: Chaabo, Ayman, de Ceaurriz, Jacques, Buisson, Corinne, Tabet, Jean-Claude, Lasne, Françoise
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Berlin/Heidelberg : Springer-Verlag 01.02.2011; Springer-Verlag; Springer
• Subjects: adrenal glands; Analytical Chemistry; Biochemistry; Biological and medical sciences; Calibration; cation exchange chromatography; Cation exchanging; Cell physiology; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Chromatographic methods and physical methods associated with chromatography; Chromatography; Chromatography, Ion Exchange; Chromatography, Liquid; corticotropin; Cosyntropin - blood; detection limit; Doping; Drugs; Exact sciences and technology; Excretion study; Food Science; Fundamental and applied biological sciences. Psychology; glucocorticoids; Humans; immunoaffinity chromatography; ionization; ions; Laboratory Medicine; Mass Spectrometry; Mathematical analysis; Molecular and cellular biology; Monitoring/Environmental Analysis; Original Paper; Other chromatographic methods; Purification; secretion; Secretion. Exocytosis; Secretions; Sensitivity and Specificity; Solid Phase Extraction; Spectrometric and optical methods; Synacthen; Tandem mass spectrometry; Tandem mass spectrometry; Excretion study; Synacthen; Doping; Performance evaluation; Solid phase extraction; Plasma; Adrenal glands; Internal standard; Product; Identification; Electrospray; Ion exchange chromatography; Detection limit; Standard curve; Peak; Release; Cation exchange; Hormone; Drug; Purification; Immunoaffinity chromatography; Secretion; Sample; Use; Ultratrace compound; Kinetic method; Liquid chromatography; Chemical ionization; Preparation; Mass spectrometry MS/MS; Simultaneous measurement
• ISSN: 1618-2642; 1618-2650; 1618-2650
• DOI: 10.1007/s00216-010-4565-z

Tetracosactide (Synacthen), a synthetic analogue of adrenocorticotropic hormone (ACTH), can be used as a doping agent to increase the secretion of glucocorticoids by adrenal glands. The only published method for anti-doping control of this drug in plasma relies on purification by immunoaffinity chromatography and LC/MS/MS analysis. Its limit of detection is 300 pg/mL, which corresponds to the peak value observed 12 h after 1 mg Synacthen IM administration. We report here a more sensitive method based on preparation of plasma by cation exchange chromatography and solid-phase extraction and analysis by LC/MS/MS with positive-mode electrospray ionization using 7-38 ACTH as internal standard. Identification of Synacthen was performed using two product ions, m/z 671.5 and m/z 223.0, from the parent [M + 5H]⁵⁺ ion, m/z 587.4. The recovery was estimated at 70%. A linear calibration curve was obtained from 25 to 600 pg/mL (R ² > 0.99). The lower limit of detection was 8 pg/mL (S/N > 3). The lower limit of quantification was 15 pg/mL (S/N > 10; CV% < 20%). The performance of the method was illustrated by an 8-h kinetic analysis of plasma samples from nine subjects submitted to IM injections of either Synacthen® (five subjects) or Synacthen® Depot, the slow-release form of the drug (four subjects). Concentrations of Synacthen between 16 and 310 pg/mL were observed. A sensitive method for quantitation of Synacthen in plasma is proposed for anti-doping control analyses.