Abstract:

A method of ultra performance liquid chromatography-photodiode array detection (UPLC-DAD) has been established
for the rapid simultaneous determination of 14 psychoactive drugs (alprazolam, estazolam, clonazepam, diazepam, phenobarbital,
midazolam maleate, triazolam, nitrazepam, barbital, secobarbital, chlordiazepoxide, lorazepam, amobarbital, and oxazepam) that
are illegally added in sleep-improving health-care foods. A ZORBAX SB-C18 column (2.1 mm × 100 mm, 1.8 μm) was applied.
Methanol-0.2% acetic acid was selected as the mobile phase in a linear gradient elution mode,with flow rate of 0.4 mL/min.
The detection wavelengths were 210 nm and 230 nm for rapid screening and quantitation. The results showed that the 14
psychoactive drugs could be effectively separated in 13.5 min, and the standard curves had good linearity over the concentration
range of 5–50 μg/mL or 10–100 μg/mL. The correlation coefficients (r) were all above 0.9995. The average recoveries varied
from 80.4%–106.2% and the detection limits were in the range of 3–6 ng for the psychoactive drugs. This developed method is
characteristics of simple operation, rapid determination, high sensitivity and excellent reproducibility so that it is suitable for the
rapid determination of d 14 illegal psychoactive drugs in sleep-improving health-care foods.

Key words: health-care food, sleep improvement, illegal addition, rapid determination, ultra performance liquid chromatography-photodiode array detection (UPLC-DAD)