Determination of testosterone esters in serum by liquid chromatography – tandem mass spectrometry (LC-MS-MS)
Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
Anabolic androgenic steroids are testosterone and its derivates. Testosterone is the most important naturally existing sex hormone for men and is used for its anabolic effects providing increased muscle mass. Testosterone is taken orally or by intramuscular injection in its ester form and are available illegally in different forms of esters. Anabolic androgenic steroids are today analyzed only in urine. To differentiate between the human natural testosterone and exogenous supply the quote natural testosterone and epitestosterone is used. Detection of testosterone esters in serum is an unmistakable proof of exogenous supply of testosterone. The aim of this thesis was to find a method for determining testosterone esters in serum and to study an extraction method possible for quantification of testosterone esters in serum.
The technique used to separate and identify the Testosterone esters was Liquid Chromatography Tandem Mass Spectrometry Electro Spray Ionisation. Parameters for chromatography and mass detection were optimized for nine testosterone esters and evaluated according to selectivity, resolution and intensity. A method that could be used for determination of testosterone esters in serum was found. The MS-method was set and at least three possible transitions for each testosterone ester were found. The best choice of column proved to be the C18 column where all the esters were separated and seven of them were base-line separated. The C18 column along with methanol and ammonium acetate buffer, 5 mM, pH 5 showed the highest sensitivity for Multiple Reaction Monitoring-detection. A gradient profile for a total runtime of 5.6 minutes was established. Two alternative extraction procedures were tested, with tert-butylmethylether or diethyl ether/ethyl acetate and both seemed to work satisfactory. Analysis of serum proved to work well and no severe interference occurred. Results from the linearity tests indicate that future quantification method in serum will be possible.
Place, publisher, year, edition, pages
2010. , 52 p.
LC-MS-MS, MRM, testosterone, testosterone esters
Analytical Chemistry Forensic Science
IdentifiersURN: urn:nbn:se:liu:diva-58045ISRN: LITH-IFM-G-EX--10/2263--SEOAI: oai:DiVA.org:liu-58045DiVA: diva2:331730
UppsokPhysics, Chemistry, Mathematics
Lood, YvonneJosefsson, Martin