High throughput and very specific screening of anabolic-androgenic steroid adulterants in healthy foods based on stable isotope labelling and flow injection analysis-tandem mass spectrometry with simultaneous monitoring proton adduct ions and chloride adduct ions

•A novel SIL-FIA-MS strategy for detecting AAS in foods was proposed.•The detection sensitivity was improved by 2–5 folds after 3-NPH labelling.•13C6-3-NPH labelled AAS were used as internal standard to correct matrix effect.•Detection specificity was guaranteed by simultaneous monitoring [M+H]+ and [M+Cl]−.•The method is high throughput, very specific, accurate with good sensitivity.