Evaluation of designer amphetamine interference in GC-MS amine confirmation procedures.

In recent years, a class of new designer drugs commonly referred to as 'bath salts' have made their way to the illicit drug market. The most common drugs encountered are designer amphetamines and cathinones. Many analytical methods for analysis and identification of bath salts have been published, but there has been little reported on their impact on existing gas chromatography-mass spectrometry (GC-MS) amine confirmation methods. Due to structural similarities, the potential exists that designer amphetamines may interfere with methods used for analysis of sympathomimetic amines. Methiopropamine, 4-fluoroamphetamine, 4-fluoromethamphetamine (4-FMA) and 4-methylamphetamine were examined for potential interference with immunoassays and GC-MS confirmation analysis utilizing three derivatization procedures: R(-)-α-methoxy-α-trifluoromethylphenylacetyl chloride (R-MTPAC), heptafluorobutyric anhydride (HFBA) and chlorodifluoroacetic anhydride (ClF(2)AA). Significant cross-reactivity was observed with all the four compounds on the Syva Emit(®) II Plus Amphetamines and Roche KIMS Amphetamines II immunoassays. Laboratories utilizing GC-MS selected-ion-monitoring confirmation methods with R-MTPAC, HFBA or ClF(2)AA derivatives could experience potential chromatographic and mass spectral interferences from 4-fluroamphetamine, 4-FMA and methiopropamine in the form of ion ratio and quantitative failures. Careful ion selection, proper selectivity and specificity studies during method validation and rigid chromatographic and spectral acceptance criteria are required to assure the robustness and accuracy of GC-MS methods.

Evaluation of abalone ß-glucuronidase substitution in current urine hydrolysis procedures.

This study examined the potential of abalone ß-glucuronidase as a viable and cost effective alternative to current hydrolysis procedures using acid, Helix pomatia ß-glucuronidase and Escherichia coli ß-glucuronidase. Abalone ß-glucuronidase successfully hydrolyzed oxazepam-glucuronide and lorazepam-glucuronide within 5% of the spiked control concentration. Benzodiazepines present in authentic urine specimens were within 20% of the concentrations obtained with the current hydrolysis procedure using H. pomatia ß-glucuronidase. JWH 018 N-(5-hydroxypentyl) ß-d-glucuronide was hydrolyzed within 10% of the control concentration. Authentic urine specimens showed improved glucuronide cleavage using abalone ß-glucuronidase with up to an 85% increase of drug concentration, compared with the results obtained using E. coli ß-glucuronidase. The JWH 018 and JWH 073 carboxylic acid metabolites also showed increased drug concentrations of up to 24%. Abalone ß-glucuronidase was able to completely hydrolyze a morphine-3-glucuronide control, but only 82% of total morphine was hydrolyzed in authentic urine specimens compared with acid hydrolysis results. Hydrolysis of codeine and hydromorphone varied between specimens, suggesting that abalone ß-glucuronidase may not be as efficient in hydrolyzing the glucuronide linkages in opioid compounds compared with acid hydrolysis. Abalone ß-glucuronidase demonstrates effectiveness as a low cost option for enzyme hydrolysis of benzodiazepines and synthetic cannabinoids.