Application of Dried Urine Spots for Non-Targeted Quadrupole Time-of-Flight Drug Screening.

The use of dried urine spots (DUS) can simplify sample handling, shipment and storage when compared to liquid urine samples. To prepare DUS, a small amount of urine is pipetted on a filter paper card. The subsequent drying of the specimen can prevent the post-sampling formation or degradation of substances (e.g., caused by bacteria). To evaluate the potential of DUS screening, 17 authentic urine samples, containing a broad range of substances, were extracted and analyzed on a Sciex TripleTOF® 5600+ System using a non-targeted screening and library searching approach. The screening results were compared to the analysis of the same urine sample in liquid form, using the same high-resolution liquid chromatography--quadrupole time-of-flight mass spectrometry method. More than 65 different legal and illegal drugs were successfully identified within the investigated 17 urine samples using the DUS screening approach. When compared to the analysis of liquid urine, the following compounds could not be identified: 1x ecgonine methyl ester, 1x nicotine, 1x promazine and 1x 11-nor-9-carboxy-∆9-tetrahydrocannabinol. Overall, 95.2% of the target substances that have been detected in liquid urine were identified correctly using the DUS approach. In conclusion, DUS screening offers a simple, cost-effective and easier sample handling alternative to the traditional use of liquid urine and provides the detection of the most important substances for forensic requirements. Furthermore, the DUS sample preparation can be fully automated (sample documentation, internal standard application and extraction).

Simultaneous quantification of delta-9-THC, THC-acid A, CBN and CBD in seized drugs using HPLC-DAD.

An HPLC-DAD method for the quantitative analysis of Δ(9)-tetrahydrocannabinol (THC), Δ(9)-tetrahydrocannabinolic acid-A (THCA-A), cannabidiol (CBD), and cannabinol (CBN) in confiscated cannabis products has been developed, fully validated and applied to analyse seized cannabis products. For determination of the THC content of plant material, this method combines quantitation of THCA-A, which is the inactive precursor of THC, and free THC. Plant material was dried, homogenized and extracted with methanol by ultrasonication. Chromatographic separation was achieved with a Waters Alliance 2695 HPLC equipped with a Merck LiChrospher 60 RP-Select B (5µm) precolumn and a Merck LiChroCart 125-4 LiChrospher 60 RP-Select B (5µm) analytical column. Analytes were detected and quantified using a Waters 2996 photo diode array detector. This method has been accepted by the public authorities of Switzerland (Bundesamt für Gesundheit, Federal Office of Public Health), and has been used to analyse 9092 samples since 2000. Since no thermal decarboxylation of THCA-A occurs, the method is highly reproducible for different cannabis materials. Two calibration ranges are used, a lower one for THC, CBN and CBD, and a higher one for THCA-A, due to its dominant presence in fresh plant material. As provider of the Swiss proficiency test, the robustness of this method has been tested over several years, and homogeneity tests even in the low calibration range (1%) show high precision (RSD≤4.3%, except CBD) and accuracy (bias≤4.1%, except CBN).