Development of a quantitative approach in blood plasma for low-dosed hallucinogens and opioids using LC-high resolution mass spectrometry

The characterization of isobaric product ions of fentanyl using multi‐stage mass spectrometry, high‐resolution mass spectrometry and isotopic labeling

“…Figure shows an example of the product ion spectrum generated from the fragmentation of the [M+H] + protonated precursor of fentanyl observed at m/ z 337 with the major structural fragments embedded. The base peak in this spectrum is observed at m/ z 188, which has been identified as a characteristic ion for the identification of fentanyl derivatives . However, based on the competing mechanisms for the loss of the N ‐phenylpropanamide neutral, previous literature has demonstrated that this peak must contain at least two isobaric product ions with different constitutional structures …”

“…For example, Feasel et al observed largely analogous collision‐induced dissociation (CID) spectra between carfentanil and remifentanil . Caspar et al discussed the value of having group‐indicating ions that might help to identify novel compounds . They recommended HRMS to help identify the elemental compositions of different fragment ions, including the fragment at m/ z 188.1439 in the case of fentanyl analogs .…”

Blood plasma level determination using an automated LC–MSn screening system and electronically stored calibrations exemplified for 22 drugs and two active metabolites often requested in emergency toxicology

“…The authors' established LLE was used for sample preparation, which was already described for several screening and quantification methods . It allowed simple, fast, and reliable extraction of all included analytes (recovery data are shown in Table S2).…”

“…According to published procedures, the authors' routine blood plasma liquid–liquid extraction (LLE) was used. Briefly, 1 mL blood plasma was mixed with 0.1 mL of IS solution (final plasma concentration, 1,000 μg/L), 2 mL saturated aqueous sodium sulfate solution, and 5 mL diethyl ether‐ethyl acetate mixture (1:1).…”

“…According to published procedures, dilution integrity was validated by spiking blank blood plasma to a final plasma concentration five‐times higher than the QC HIGH plasma concentrations (Table ). After 1:10 dilution with blank blood plasma, the samples were extracted as described above.…”