A validated dilute-and-shoot LC–MS-MS urine screening for the analysis of 95 illicit drugs and medicines: Insights from clinical and forensic Brazilian cases.

This article focuses on the development, optimization, and validation of a comprehensive liquid chromatography–tandem mass spectrometry (LC–MS-MS) screening method using the dilute-and-shoot technique for the analysis of 95 illicit drugs and medicines in urine samples. Validated according to the American Academy of Forensic Science (AAFS) ANSI/ASB Standard 036 guideline, the method demonstrated satisfactory sensitivity, precision, and accuracy, with a total chromatographic run time of 7.5 minutes. Applied to 839 urine samples from clinical and forensic cases in Brazil, the method detected substances in 90.9% of samples, with lidocaine, acetaminophen, and cocaine metabolites being the most prevalent. The study highlights the method's utility for poisoning diagnosis, substance use verification, and forensic investigations, providing valuable data to inform public health and safety policies in Brazil.