Various capsule samples contained mixtures of PGL and codeine, a derivative of morphine that can cause serious respiratory failure. Moreover, results included either low drug amounts intended to mislead consumers or high concentrations beyond expected levels, posing toxicity risks. Overall, the analytical examination revealed poor practices in smuggled pharmaceuticals threatening public health and safety. These current chromatographic methods demonstrated significant performance characteristics for detecting PGL in seized samples and showed reliable quantitative and qualitative analysis. The analytical capabilities allowed simultaneous detection of multiple compounds, including pregabalin, codeine, gabapentin and paracetamol.
4 Sample preparation
- The chromatographic separation, combined with LCMS confirmation, provided accurate and dependable results for both powder and capsule formulations, making it an ideal tool for forensic analysis and quality control purposes.
- In this context, it is worth mentioning the definition of the term abuse, which is defined as “the substance that is used for nontherapeutic purposes to obtain psychotropic (e.g., euphoric, sedative, or anxiolytic) effects” (Smith et al., 2013).
- System suitability of six independent preparations of PGL reference standard (2 mg/mL) for UPLC-PDA method.
- The HPLC-UV method recommended by the British Pharmacopoeia (BP) (British Pharmacopoeia, 2022) was upgraded to UPLC-PDA and then validated.
- She cannot afford Lyrica at $7/pill, but the generic version is not available in the USA until 2018.
Of these, 18.4% (25/136) of patients had a history of substance abuse compared with 14.0% (1884/13,480) in the full population. When sample extracts were injected into the LC column and eluted into the mass spectrometer, the transitions of PGL and monitored adulterants were automatically detected and peaks were produced in the chromatograms. By comparing retention times and peak areas to known standards, PGL, along with multiple adulterants in several seized capsule and powder samples, were distinguishable. LC-MS/MS analysis was performed to investigate the seized capsules and powder samples to identify any potential adulterants. The instrument was operated in multiple reaction monitoring (MRM) mode for targeted quantitative analysis.
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Catriona Matheson, professor in substance use at the University of Stirling and former chair of the Scottish government’s Drug Deaths Taskforce, tells The Pharmaceutical Journal that it would be helpful to investigate whether gabapentinoid use across Scotland could be audited. There is concern that the increase lyrica prescription online in use of pregabalin is in response to decreasing trends in opioid prescribing4. The original contributions presented in the study are included in the article/supplementary material, further inquiries can be directed to the corresponding author.
Pregabalin, which is licensed to treat epilepsy, neuropathic pain and anxiety, hit the headlines in March 2024 after The Sunday Times reported that it has the fastest-rising death toll of any drug in the UK. LC-MS/MS analysis revealed distinct fragmentation patterns characteristic of each analyte under optimized collision-induced dissociation (CID) conditions, validated against reference standards and published fragmentation patterns. The powder samples for raw material were visually investigated which demonstrated irrational results. A noticeable discrepancy was observed between different powder samples in terms of crystal size and shape. Irregular crystal structures were noticed compared to the well-defined structures typically expected for pure PGL. This observation might indicate a lack of homogeneity and potentially confirms poor manufacturing practices.
1H NMR spectrum (600 MHz, D2O) of pregabalin powder representative sample (A) with zoom-in from 1 to 3 ppm (B), showing characteristic proton signals of pregabalin. A Waters® ACQUITY UPLC-PDA system was used for separation, equipped with a Phenomenex C18 column (2.1 × 50 mm, 1.8 µm). Structural nuclear magnetic resonance (NMR) elucidation was performed by JEOL JNM-ECA600II NMR (deuterium oxide (D2O) solvent, tetramethylsilane (TMS) as a reference).
