Analytical grade methanol

Technical grade acetone was purchased from VWR (Haasrode, Belgium). Analytical grade acetone, analytical grade methanol, HPLC gradient grade acetonitrile, HPLC gradient grade methanol, HPLC grade phosphoric acid, HPLC grade formic acid and LC-MS grade formic acid were purchased from VWR International (Fontenay-Sous-Bois, Paris, France). HPLC grade n-otanol and LC-MS grade acetonitrile were purchased from Merck (KGaA, Darmstadt, Germany). Aa grade ethanol (≥99.5%) was purchased from Altia OyJ (Helsinki, Finland). Ultra-pure type I water was purified with Merck Millipore Synergy UV system.

DBP (CAS No 84-74-2, purity > 99%), corn oil (CAS No 8001-30-7), analytical grade standards of testosterone, androstenedione, corticosterone and progesterone, isotope-labelled testosterone-d3, corticosterone-d4 and progesterone-¹³C5, SIGMAFAST™ protease inhibitor tablets, DAPI, bovine serum albumin (BSA), and DPX-mounting medium were all purchased from Sigma Aldrich (St. Louis, MO, USA). Tween 20, NaCl and Tris-HCl, as well as LC-MS grade water, methanol and acetonitrile were all purchased from Fisher (Loughborough, UK). Ammonium fluoride was purchased from Honeywell Research Chemicals (Morris Plains, NJ, USA). HPLC grade ethyl acetate was purchased from Rathburn Chemicals Ltd. (Walkerburn, UK). Phosphate buffered saline (PBS) was purchased from Gibco, Life Technologies Europe (Bleiswijk, The Netherlands). Triton X-100 and analytical grade methanol (used for immunohistochemistry) were purchased from VWR international (Radnor, PA, USA). Normal goat serum, F(ab’)2 goat anti-mouse immunoglobulin G was purchased from Invitrogen (Waltham, MA, USA). TBS was purchased from Medicago AB (Uppsala, Sweden). Sodium deoxycholate was purchased from Alfa Aesar ThermoFisher GmbH (Kandel, Germany). Dry milk was purchased from Cell signalling Technology (Danvers, MA, USA). The chemiluminescence ECL kit was purchased from Biorad (Hercules, CA, USA).