Development of a specific fragmentation pattern-based quadrupole-Orbitrap™ mass spectrometry method to screen drugs in illicit products

Application of a simultaneous screening method for the detection of new psychoactive substances in various matrix samples using liquid chromatography/electrospray ionization tandem mass spectrometry and liquid chromatography/quadrupole time-of-flight mass spectrometry

RATIONALE

Recently, new psychoactive substances (NPS) have emerged as a public health risk. Particularly, their chemical structures are modified to avoid detection. Synthetic NPS with effects similar to those of illegal drugs have been recently detected and synthesized worldwide, including MDMB-FUBINACA and APINAC, making it essential to rapidly and accurately detect NPS.

METHODS

Fourteen NPS with similar structures were selected and their structures identified using ¹ H and ¹³ C NMR spectroscopy. Additionally, we proposed the fragmentation pattern of each compound using liquid chromatography/quadrupole time-of-flight mass spectrometry (LC/QTOF-MS). A simultaneous analytical method using liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS) was also developed and applied to real samples to detect the 14 NPS. The method was validated based on the specificity, linearity, limit of detection (LOD), limit of quantification (LOQ), precision, accuracy, matrix effect, and stability according to international validation guidelines.

RESULTS

The established method was used to screen 65 different matrix samples using LC/ESI-MS/MS. By comparing the calculated product ion ratios with those of standards, 2C-B in one of the real samples and 5F-MDMB-PICA in 20 samples were identified. For re-confirmation of detected compounds, the fragmentation pattern of each compound was compared with that of each standard using LC/QTOF-MS.

CONCLUSIONS

In this study, LC/QTOF-MS data were used to elucidate the structures and fragmentation patterns of 14 NPS. A simultaneous method was developed using LC/ESI-MS/MS, which was applied to 65 real samples. The presented method and results can assist in ensuring the safety of public health from illegal adulteration.

Development of a fragmentation pattern of synthetic cannabinoids based on electrospray ionization mass spectrometry in positive ion mode to screen synthetic cannabinoids in illicit products

To explore the MS fragmentation pattern of synthetic cannabinoids by electrospray ionization mass spectrometry, twenty-seven synthetic cannabinoids were systematically investigated by liquid chromatography coupled to high-resolution quadrupole Orbitrap mass spectrometry(LC-Q-Orbitrap/MS)with positive mode of electrospray ionization. Based on tandem multistage MS and high resolution MS data, MS fragmentation pattern of synthetic cannabinoids was summarized. The cleavage of CC bonds next to the oxygen at the side chain on the C-3 position of synthetic cannabinoids was the characteristic fragmentation pathway of synthetic cannabinoids in the positive mode of electrospray ionization. When the synthetic cannabinoids with a 3-carbamoylpropyl-indole/indazole structure, NH₃, CO, NH₂CHO and CH₂(CH₃)₂ were easy to lose to form different ions. While when the synthetic cannabinoids with a 3-carboxamide-indole/indazole structure, the side chain on the C-3 position was susceptible to γ-cleavage. In addition, this MS fragmentation pattern was applied to quickly screen whether electronic cigarette oil and tobacco from drug cases contain synthetic cannabinoids. This kind of compounds had strong fragmentation pattern, which provided new evidence for the rapid structure identification of synthetic cannabinoids.