Derivatisation and gas chromatography-chemical ionisation mass spectrometry of selected synthetic and natural endocrine disruptive chemicals

Methods for ultra trace detection of endocrine disruptive chemicals (EDCs) are needed because of their low levels of impact. Twenty-one EDCs were selected, including 17beta-estradiol, 17alpha-ethinylestradiol, 17beta-testosterone and bisphenol A. Derivatisation with eight different fluorine containing compounds was examined. All EDCs could be derivatised automatedly (autosampler) with heptafluorobutyric acid (HFB) anhydride and trifluoroacetic acid (TFA) anhydride, respectively. The detection of these HFB and TFA derivatives in different chemical ionisation modes was studied. Fourteen different reagent gases, including methane, ammonia, acetone and water, were tested with the HFB and TFA derivatives in the negative chemical ionisation mode. Furthermore both types of derivatives were measured in positive chemical ionisation mode. Methane or water provide a good detection of all 21 TFA derivatives and create mass spectra with few fragmentation and characteristic mass peaks. This could serve as a basis for tandem or multiple mass spectrometric measurements.

Simultaneous determination of 6-oxo-prostaglandin F1 alpha and 2,3-dinor-6-oxo-prostaglandin F1 alpha in biological fluids by stable isotope dilution and negative ion chemical ionization mass spectrometry

A stable isotope dilution assay for the simultaneous determination of two metabolites of prostacyclin (1), 6-oxo-prostaglandin F1 alpha (2a) and 2,3-dinor-6-oxo-prostaglandin F1 alpha (3a), in human seminal fluid and human urine is described. A new chemical total synthesis of deuterated internal standard, 18,18,19,19-(2H4)-2,3-dinor-6-oxo-PGF1 alpha (3b), is presented and enables specific and sensitive quantification based on negative ion chemical ionization mass spectrometry. 2a and 3a were analysed as their methoxime pentafluorobenzyl ester tris(trimethylsilyl) ether derivatives in the selected ion monitoring mode registrating the [M-181]- fragments with a detection limit for both prostanoids of 10 pg per injection. The two metabolites occur in human seminal fluid in very low concentrations (2a: 2.8 ng ml-1; 3a: 1.7 ng ml-1) and cannot contribute significantly to the urinary metabolite levels which are in the range of 108-265 ng/24 h for 3a and 124-574 ng/24 h for 2a.

[Detection of pentazocin (Fortral) in human urine: gas chromatographic/mass spectrometric studies]

After oral application of pentacozine (Fortral) besides the unchanged drug some further excretion products were detected by glc/ms in human urine. For their identification e.i.-and c.i.-mass-spectrometry as well as the just recently available FAB-technique were employed. All analyses were performed on a VG-Micromass 7035; the samples were introduced in the ion source via a fused silica, bonded phase capillary column (30 metres; DB-1 J + W, Inc.). The analytical profiles of the pure substance and some metabolites are reported as well as the behaviour of the pure substance on acidic hydrolyzation.

[FAB (fast atom bombardment)-mass spectrometry. A new study method in the hands of the (forensic) toxicologist]

The FAB (Fast Atom Bombardment)-mass spectrometric ionization technique, which has now been available for about 1 year, has been successfully employed in forensic toxicology. The mass spectral behaviour of some representative drug-glucuronides (Codeine, p-Nitrophenol and 2-Phenyl-1-propanol) were studied by positive- and negative-ion-FAB-MS. The presented promising results may be of some interest, not only for the analytical toxicologist.