Cobas e 411 auto analyser

The Bone Metabolism Group in the Faculty of Medicine, Dentistry and Health at Sheffield University measured plasma total 25-hydroxyvitamin D using an electrochemiluminescence binding method on a COBAS e 411auto analyser (Roche Diagnostics, Germany). The inter assay CV for total vitamin D was 5.7 %.

Blood samples obtained by venipuncture were centrifuged, within 30 minutes from the collection, for 10 min at 3500 rpm, 4°C. Aliquots of each serum were frozen at −80°C and stored for subsequent assays of AMH, FSH and E2. To measure serum AMH levels, AMH-Gen II ELISA assay kit (Beckman Coulter) was used. The lowest detection limit of AMH is 0.08 ng/mL and the intra and interassay coefficients of variation below 3.4% and 4.0% respectively. The ECLIA method used to measure the levels of serum FSH and E2 by COBAS e411 auto-analyser (Roche Diagnostics). The lowest detection limit for FSH is 0.100 IU/L, with the intra- and interassay coefficients of variation below 2.6% and 3.5% respectively. The lowest detection limit for E2 is 18.4 pmol/L, with the intra- and interassay coefficients of variation of 2% and 3%, respectively.
Giving the poor reliability of the FSH value in presence of Estradiol levels greater than 70 pg/mL, women with basal E2 levels greater than this cut off were asked to come back at the beginning of the subsequent menstrual cycle, and their data were excluded from the analysis.