Thin-layer chromatography, with fluorescence detection, of benzodiazepines and tricyclic antidepressants in serum from emergency-room patients.

We describe a rapid, sensitive procedure for detecting benzodiazepines and tricyclic antidepressants in serum. After the compounds are adsorbed on charcoal and eluted with an organic solvent mixture, the drugs are thin-layer chromatographed and detected by their fluorescence. Because it is so fast and easy (turn-around time of about 1 h), the method can be used for emergency toxicology screening. An analysis requires 1.0 mL of serum, and the limit of detection for each of the drugs is about 0.75 mg/L. The procedure is sensitive enough to allow the use of serum instead of urine for the detection of these drugs, because serum has certain advantages over urine as the sample and better reflects the state of the patient's toxicity.