The determination of budesonide and fluticasone in human sputum samples collected from COPD patients using LC-MS/MS

► We validated an LC-MS/MS method for budesonide and fluticasone in human sputum. ► The LLOQ was 5 nM. ► Intra- and inter-run RSD were within 6.9% (budesonide) and 8.0% (fluticasone). ► The accuracy was within ±15%. ► The method was applied to clinical sputum samples.