Fiorenza Farè

Validation of a GC/MS method for the determination of tramadol in human plasma after intravenous bolus ☆

Tramadol quantitative determination by gas chromatography-mass spectrometry (GC/MS) using nefopam hydrochloride as internal standard (IS) and two calibration curves because of the large range of concentration attended in the plasmatic samples is described. Plasma samples drawn from subjects in postoperative period treated with two different initial intravenous (iv) bolus of tramadol (50 and 100 mg) followed by tramadol at the same infusion rate (12 mg h(-1)) are analysed. We operated for the qualitative analysis in Scan mode while for the quantitative analysis in SIM mode, selecting the ion m/z 58 for tramadol and m/z 179 for IS. The limit of detection (LOD) was 0.01 microg ml(-1) and the limit of quantification was 0.04 microg ml(-1).

Determination of primary active constituents in Cannabis preparations by high-resolution gas chromatography/flame ionization detection and high-performance liquid chromatography/UV detection

Abstract For a complete quantitative analysis of primary active constituents in Cannabis preparations Δ 9 -tetrahydrocannabinol (THC), cannabidiol (CBD) and cannabinol (CBN), we have compared two different chromatographic techniques, high-resolution gas chromatography (HRGC)/flame ionization detection (FID) and high-performance liquid chromatography (HPLC)/UV. The two different methods have been validated using crude drug (hashish) with methyloleate and tetraphenylethylene as internal standard for HRGC/FID and HPLC/UV, respectively.

Unexpected Variation of the Codeine/Morphine Ratio Following Fatal Heroin Overdose

Postmortem samples from 14 cases of suspected heroin overdose were subjected to a preliminary systematic toxicological analysis in order to highlight the presence of unknown exogenous compounds (e.g., drugs of abuse, alcohol) that may have played a role in the mechanism of death. This analysis unveiled histories of poly-drug use in seven of the cases under investigation. Moreover, the concentrations of morphine and codeine in the brain were also investigated, and the results were compared with the data obtained from the blood specimens. The concentration of morphine in blood ranged from 33 to 688 ng/mL, while the concentration of codeine ranged from 0 to 193 ng/mL. However, in the brain, the concentration of morphine was found to be between 85 and 396 ng/g, while the levels of codeine ranged from 11 to 160 ng/g. The codeine/morphine ratio in the blood ranged from 0.043 to 0.619; however, in the brain, the same ratio was found to be between 0.129 and 0.552. In most cases, a significantly higher codeine/morphine ratio was found in the brain, suggesting the accumulation of codeine in brain tissue due its high lipophilicity as compared with morphine.

A case of fatal intoxication from metformin

A case of fatal intoxication from metformin is presented. The decedent was an obese 58‐year‐old‐woman with type II diabetes, in whom severe lactic acidosis secondary to metformin accumulation was precipitated by acute renal failure. She had been on metformin 500 mg twice a day. Postmortem blood was deproteinated with acetonitrile, washed with dichloromethane, and the resulting supernatant injected into high‐performance liquid chromatography system. Separation was performed on a analytical 125 × 4 mm i.d. RP‐8 column. The wavelength was set at 235 nm. The mobile phase was acetonitrile (40%), sodium lauryl sulfate, and sodium dihydrogen phosphate adjusted to pH 5.1 (60%) at a flow rate of 1.0 mL/min. The concentration of metformin in postmortem blood was 77.3 μg/mL. The qualitative result was also confirmed by LC/APCI/MS/MS analysis.

Analysis of fluid extracts obtained from Papaver rhoeas petals contaminated with Papaver bracteatum petals.

In this paper, we report a case of misidentification of medicinal plants involving dried petals of Papaver rhoeas (red poppy) contaminated with Papaver bracteatum (scarlet poppy) petals. Preliminary TLC analysis indicated the presence of thebaine either in the fluid extracts or in the petals. It was therefore necessary to carry out an accurate botanic examination of the plant material, which revealed contamination of the red poppy petals with scarlet poppy petals. Moreover, to confirm the adulteration, we developed and validated an efficient, reversed-phase ion pair HPLC method for determination of the alkaloids specific for the Papaver species. Six petal batches and five commercial fluid extracts were analyzed. Only one petal batch from Iran contained thebaine and its analogue oripavine while the alkaloids typical for the Papaver bracteatum species were identified in all fluid extracts, meaning that they were all prepared with contaminated petals.

Validation Study of Analysis of 1-Phenyl-2-Propanone in Illicit Methamphetamine Samples by Dynamic Headspace Gas Chromatography Mass Spectrometry

A new method based on dynamic headspace sampling (DHS) coupled to GC/MS analysis was developed, optimized and validated for the analysis of 1-phenyl-2-propanone (P2P) in illicit methamphetamine (MAMP) samples. The DHS parameters were investigated to reach the sensitivity suitable for this kind of analysis. The method showed of a good specificity, linearity, accuracy, precision and robustness. The analysis of ten MAMP samples seized by the judicial authority was carried out. P2P was found in all the seizure, confirming that P2P is the starting compound of the synthesis of amphetamines.

Determination of 6-Monoacetyl-Morphine (6-MAM) in Brain Samples from Heroin Fatalities

Objective: Post-mortem brain samples from 15 deceased patients whose death was heroin related, were analyzed to determine 6-monoacetyl-morphine (6-MAM) concentrations. The samples belonged to people died between 2008 and 2014. The first eight samples were also analyzed in 2012 to determine only morphine and codeine levels. Method: A GC/MS method was studied in order to enhance sensitivity, thus helping the determination of 6-MAM whose detection is in most cases difficult because of the complexity of the biological matrix. The analytical method was validated using deuterated internal standards (IS-D3, morphine-D3 and codeine-D3) and it showed adequate specificity, linearity, LOD, LOQ precision and accuracy for the determination of the analyte of interest. Results: 6-MAM was evidenced only in the more recent samples, thus pointing out its low stability. Its concentration ranged from 15.6 to 28.9 ng/g. Morphine and codeine was also determined and a comparison was carried out between the blood and the brain levels of the three analytes. Moreover a parallel was established between the concentrations of morphine and codeine found in the brain in 2012 and 2015. Conclusion: 6-MAM determination in the brain is particularly important when discriminating between morphine assumption and heroin abuse. In fact in the cases in which it is not detectable in the blood it can be present in the brain. It was noticed that the concentrations of morphine found in the brain in 2015 are higher respect to the levels of 2012; a possible explanation could be that 6-MAM originally present in the brain has hydrolyzed to morphine, thus increasing its levels.

Determination of 1-phenyl-2-propanone (P2P) by HS-GC/MS in a material sold as “wet amphetamine”

In this paper, we describe the approach to the characterization of an unusual material seized by the judicial authority, near Brescia City in Northern Italy. Usual analyses such as thin-layer chromatography, gas chromatography (GC)–flame ionization detection, and GC/mass spectrometry (MS) did not show the presence of drugs of abuse, in particular amphetamine-like compounds. The major solid component was identified as cornstarch; then taking into account the strong aromatic scent of the seized material; a preliminary experiment for volatile organic compounds was carried out by headspace (HS)-GC/MS. This analysis tentatively evidenced the presence of 1-phenyl-2-propanone (P2P), an amphetamine precursor. Therefore, we developed and optimized a new analytical method for determination of P2P in seized materials by HS-GC/MS. We also synthesized P2P, with the permission of the Ministry of Health, to have it as reference standard, because of its being illegal and the difficulty in obtaining it. This case had some analogies with the cases referred to as “wet amphetamine” by the judicial authority, in which amphetamines are sold mixed with P2P. The possible use of the material could be the production of tablets made of cornstarch with an aromatic scent similar to that of amphetamines to deceive consumers and to sell them as a drug of abuse.

Characterization of the Volatile Components of Cannabis Preparations bySolid-Phase Microextraction Coupled to Headspace-Gas Chromatographywith Mass Detector (SPME-HSGC/MS)

Solid phase microextraction coupled to headspace sampling and GC/MS technique was applied to the characterization of the volatile components of several Cannabis preparations (hashish). Different parameters of the analytical method (fiber, coating thickness, sampling and exposition temperatures, sample preparation) were evaluated to optimize the characterization of the volatile components. a-Pinene, s-myrcene, limonene, 4-carene, trans-3(10) caren-2-ol, 4,7,7-trimethylbicyclo [4.1.0] heptan-3-ol, caryophyllene, s-humulene, azulene, gurjunene, ledene and caryophyllene oxide were identified among the volatile components of all hashish preparations. Moreover, a suitable internal standard (nonane) was chosen, the reproducibility and linearity of the method were evaluated in order to carry out the quantitative determination of caryphyllene, the most abundant volatile terpene. Its quantity ranged from 800 to 3000 µg/g.

Determination of Propofol by GC/MS and Fast GC/MS-TOF in Two Cases of Poisoning

Two cases of suspected acute and lethal intoxication caused by propofol were delivered by the judicial authority to the Department of Sciences for Health Promotion and Mother-Child Care in Palermo, Sicily. In the first case a female nurse was found in a hotel room, where she lived with her mother; four 10 mg/mL vials and two 20 mg/mL vials of propofol were found near the decedent along with syringes and needles. In the second case a male nurse was found in the operating room of a hospital, along with a used syringe. In both cases a preliminary systematic and toxicological analysis indicated the presence of propofol in the blood and urine. As a result, a method for the quantitative determination of propofol in biological fluids was optimized and validated using a liquid-liquid extraction protocol followed by GC/MS and fast GC/MS-TOF. In the first case, the concentration of propofol in blood was determined to be 8.1 μg/mL while the concentration of propofol in the second case was calculated at 1.2 μg/mL. Additionally, the tissue distribution of propofol was determined for both cases. Brain and liver concentrations of propofol were, respectively, 31.1 and 52.2 μg/g in Case 1 and 4.7 and 49.1 μg/g in Case 2. Data emerging from the autopsy findings, histopathological exams as well as the toxicological results aided in establishing that the deaths were due to poisoning, however, the manner of death in each were different: homicide in Case 1 and suicide in Case 2.