A convenient thin-layer chromatographic screening method for acetaminophen in serum.

A thin-layer chromatographic screening procedure for acetaminophen in serum was developed that meets the clinical need to identify candidates for antidotal therapy within the critical first 24 hr after ingestion. The key feature of this approach is the use of a detection reagent containing Fe(III) and 2,4,6-tris-(2'-pyridyl)-s-triazine (TPTZ). Acetaminophen on the plate reduces the Fe(III) to Fe(II), which then forms an intensely blue-colored complex with the TPTZ. Concentrations as low as 3 to 4 mg/L can be detected and the procedure is free of interference from 38 other common drugs and metabolites.