The drug 25I-NBOH, a new psychoactive substance (NPS), breaks down in the hot injector of a gas chromatograph-mass spectrometer (GC-MS), a common forensic tool, creating misleading byproducts. The main breakdown product is 2C-I, with a smaller amount of an ortho-phenolic benzyl ether (o-PBE) whose exact form depends on the solvent used. Adjusting the injector temperature, split ratio, or flow rate did not prevent this thermal degradation. Thermal analysis showed that 25I-NBOH has a narrow temperature range between melting and decomposing, making it unstable. Derivatization successfully prevented the degradation, allowing accurate GC-MS analysis.
25I-NBOH, a novel psychoactive substance found on blotter paper in Brazil, can be misidentified as 2C-I by routine gas chromatography–mass spectrometry (GC–MS) because it degrades into 2C-I inside the injector unless a derivatization procedure is used. A slight adjustment to the standard GC–MS method—shortening the solvent delay window—enables detection of an additional early chromatographic peak from the degradation, allowing distinction between 25I-NBOH and 2C-I without derivatization and preventing misidentification.