A rapid and sensitive method for the identification and quantification of quintrione residue in brown rice, rice husk, and rice straw matrices was developed and validated. Samples were extracted with acetonitrile, purified with octadecylsilane (C18) and graphitized carbon black (GCB) sorbents, and quantified using ultrahigh-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS). The developed method exhibited excellent linearity (R2 ≥ 0.9988), and the limit of quantitation was 2 μg/kg in all matrices. The method...