Endocrine Abstracts

Physiological circulating concentrations of estrogens are very low in men and postmenopausal women (<50 pg/ml), which presenting analytical challenges. Immunoassays can detect as low as 30 pg/ml, but cross-reactivity is a concern. Liquid chromatography–tandem mass spectrometry (LC–MS/MS) offers greater specificity than immunoassays, but ionisation of estrogens is inefficient. Derivatisation, which introduces charged moieties, may enhance ionisation. Dansylated de...