Synthesis of analogs of lysergic acid diethylamide

Conclusions A number of N-methyl-N[(-(-Indolyl)ethyl]glycine amides, representing analogs of lysergic acid diethylamide, were obtained.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2613–2614, November, 1972.     

Chromatographic and mass spectrometric methods for determination of lysergic acid diethylamide (LSD) and metabolites in body fluids.

Continued illicit use of the potent psychedelic drug lysergic acid diethylamide (LSD) has stimulated efforts to develop effective analytical methods for detection of the drug and its metabolites in body fluids from suspected LSD users. Recently reported methods based on gas and liquid chromatography, combined with single- and multiple-stage mass spectral analysis, now permit accurate detection and quantitation of LSD at sub-nanogram/milliliter concentrations.     

Detection of lysergic acid diethylamide, delta-9-tetrahydrocannabinol and related compounds by plasma chromatography.

Plasma chromatography as a method for ultratrace qualitative and quantitative detection of organic compounds is especially well suited for detection of gas chromatographic effluents. The optimum range of sample quantity is 10-6 to 10-12 g for detection and identification of a compound by use of its characteristic positive and negative mobility spectra. The type of reference mobility spectra produced by alkanes, aromatics, esters, halogenated compounds, nitrogenated compounds and organic acids have been previously reported. This study presents the reference mobility spectra produced for lysergic acid diethylamide (LSD), delta-9-tetrahydrocannabinol (delta-9-THC), digitoxigenin and several biochemical compounds of research significance. LSD and delat-9-THC in a mixture can be detected and identified by plasma chromatography positive mobility spectra in quantities of 10-7 g or less. All the compounds investigated in this study display strong MH-+ ions along with other ions primarily of the type (M)NO-+, (M)2H-+. None of these compounds exhibits negative mobility spectra.     

Gas chromatographic determination of 2-ethylhexanoic acid in urine as its pentafluorobenzyl ester

A gas chromatographic (GC) method was developed for the determination of 2-ethylhexanoic acid (2-EHA), initially in the urine of animals, but subsequently in samples of urine from sawmill workers in order to evaluate their exposure to 2-EHA which is used as a wood preservative. The 2-EHA was derivatised to the pentafluorobenzyl ester, which was then analysed by means of a cross-linked methyl silicone GC column with electron capture detection. Gas chromatography-mass spectrometry was used to confirm the identity of the GC peaks. The analytical range of the method was 0.03-2.70 mmol of 2-EHA per mol of creatinine in urine and the limit of detection was 0.01 mmol per mol of creatinine. The recovery of 2-EHA was 81-90% with a coefficient of variation of 9.8%. The amount of 2-EHA excreted in urine was corrected for the excretion of creatinine. The concentration of 2-EHA in the urine of the workers studied varied from 0.01 to 5.40 mmol per mol of creatinine; the median was 0.1 mmol per mol of creatinine.     

Studies on lysergic acid diethylamide and related compounds—VI: Steric requirements of von braun reaction

It has been shown that in the ergot alkaloid series the von Braun reaction is hindered if there is a substituent which is 1,3-diaxial with respect to the nitrogen lone pair in the prefered conformation.     

Sensitive determination of D-lactic acid and L-lactic acid in urine by high-performance liquid chromatography-tandem mass spectrometry

d ‐Lactic acid in urine originates mainly from bacterial production in the intestinal tract. Increased d ‐lactate excretion as observed in patients affected by short bowel syndrome or necrotizing enterocolitis reflects d ‐lactic overproduction. Therefore, there is a need for a reliable and sensitive method able to detect d ‐lactic acid even at subclinical elevation levels. A new and highly sensitive method for the simultaneous determination of l ‐ and d ‐lactic acid by a two‐step procedure has been developed. This method is based on the concentration of lactic acid enantiomers from urine by supported liquid extraction followed by high‐performance liquid chromatography–tandem mass spectrometry. The separation was achieved by the use of an Astec Chirobiotic? R chiral column under isocratic conditions. The calibration curves were linear over the ranges of 2–400 and 0.5–100 µmol/L respectively for l ‐ and d ‐lactic acid. The limit of detection of d ‐lactic acid was 0.125 µmol/L and its limit of quantification was 0.5 µmol/L. The overall accuracy and precision were well within 10% of the nominal values. The developed method is suitable for production of reference values in children and could be applied for accurate routine analysis. Copyright © 2011 John Wiley & Sons, Ltd.     

Voltammetric determination of thiodiglycolic acid in urine

In urine the level of thiodiglycolic acid (TDGA) is a sensitive indicator of exposure of the human organism to some physiologically active or toxic substances, gases and vapors. The determination of TDGA by use of a voltammetric method based on electroreduction of TDGA in acidic solution at the hanging mercury drop electrode has been developed and practically tested. In order to eliminate the matrix effect of urine, prior to voltammetric measurement the samples are eluted from a small column of PVC powder. The method is simple, low cost, rapid and sensitive, appropriate for the needs of occupational medicine.     

Gas chromatographic determination of guanadrel in plasma and urine

To evaluate the pharmacokinetics and drug availability from various dosage formulations, a method for the determination of guanadrel, (1,4-dioxaspiro[4,5]dec-2-ylmethyl)guanidine, in plasma and urine was required. A gas chromatographic procedure, based on formation of a hexafluoroacetylacetone derivative in a two-phase system of water and toluene, was developed. The limit of determination of the method is 5 ng/ml guanadrel in plasma and 15 ng/ml guanadrel in urine. Statistical analyses indicate average recoveries of 98.1 +/- 18.0 and 104.4 +/- 15.6% from plasma and urine, respectively. Mass spectrometric analyses, in conjunction with gas chromatography, confirmed the specificity of the method for intact drug. The procedure was applied successfully to drug absorption studies in humans.     

Analysis of lysergic acid amide in human serum and urine after ingestion of Argyreia nervosa seeds

The ergot alkaloid lysergic acid amide (LSA) is a secondary plant constituent in a number of plants, but it is mainly present in considerable amounts in Convolvulaceae, like Argyreia nervosa. Due to its close structural similarity to lysergic acid diethylamide, LSA is considered as psychedelic and therefore promoted as so-called “legal high” in various internet forums. During a human behavioral study with orally administered seeds of A. nervosa, blood and urine samples were obtained. The present study describes the validation of a sensitive and robust high performance liquid chromatography method with fluorescence detection, which was applied to the study samples. The limit of detection (LOD) and lower limit of quantification in human serum were 0.05 and 0.17 ng/mL, respectively, and in urine, the LOD was 0.15 ng/mL. Intra- and interday precision and accuracy were below 15 % relative standard deviation with a bias better than ±15 %. No conversion of LSA to its epimer iso-LSA was noted during analyses. The LSA concentrations in the authentic human serum samples were in the range of 0.66 to 3.15 ng/mL approximately 2 h after ingestion. In urine, LSA could be found 1–24 h after ingestion; after 48 h, no LSA could be detected. The LSA epimer iso-LSA was also detected in serum and urine in varying ratios. In conclusion, LSA serum levels in the low nanogram per milliliter range correlated with severe vegetative adverse effects (nausea, weakness, fatigue, tremor, blood pressure elevation) and a psychosis-like state, which led to study termination.     

Inductively coupled plasma mass spectrometric determination of molybdenum in urine

A method was developed for the determination of molybdenum (Mo) in human urine by direct dilution of the sample in doubly distilled water with 1% HNO3 (v/v) and inductively coupled mass spectrometry (ICP-MS). In and Y were used as internal standards. Since (98)Mo provides a higher sensitivity, it was chosen as the reference isotope. The influence of different factors, such as sample dilution, HNO3 concentration and the stability of the analyte were evaluated. The detection limit (LOD) was assessed at 0.2 microg/L Mo, while the lower limit of quantification (LOQ) was 0.6 microg/L. Recoveries ranged between 97.2 and 100.7% from solutions containing from 10 to 50 microg/L Mo. Linear calibration curves were generated from 2.1 and 52.1 microg/L with coefficients of variation (CV ) ranging from 1.62 to 3.56%. In order to establish reference values (RV) for molybdenum, the procedure presented here was used to determine Mo in the urine of a population group living in Tuscany, Italy.     

Gas chromatographic determination of aldicarb and its metabolites in urine

A method is described for the determination of aldicarb and its metabolites (the sulphoxide and sulphone) in urine by gas chromatography with flame photometric detection (GC-FPD). The sample was concentrated with a column containing activated charcoal and Florisil, and then eluted with dichloromethane-acetone (1:1, v/v). The aldicarb and aldicarb sulphoxide in the eluate solution were oxidized to aldicarb sulphone and the total sulphone concentration was determined by GC-FPD after extraction with dichloromethane and clean-up with an activated charcoal column. The detection limit was 0.0024 mg/l. The mean recoveries from spiked urine in the range 0.04-0.12 mg/l were 90.9%, 86.6%, 92.6% for aldicarb, aldicarb sulphoxide and aldicarb sulphone, respectively.