[Screening for tetracyclic benzodiazepines using EMIT-st (benzodiazepines) and TDx]

The article reports threshold ranges and detection limits for the screening of tetracyclic benzodiazepines (adinazolam, alprazolam, brotizolam, estazolam, loprazolam, midazolam, triazolam and many metabolites) using the EMIT-st and TDx system (FPIA). In most cases, the cross reactivities of the two systems are comparable, but there are also remarkable differences. Detection limits are mainly in the range between 0.2 and 0.5 mg/l but, in some cases, the limits are also considerably higher. The within-day precision is 1.1% (TDx) and 16.5% (EMIT-st); day-to-day precision is 4.7% (TDx) and 12.6% (EMIT-st), respectively.