The detection of tubazid and saliuzid metabolites in internal organs and biological fluids

Detection of tubaside and saluside metabolites by methanol extraction from homogenized object with subsequent investigation by UV spectrophotometry, microcrystalloscopy, thin-layer chromatography and coloured reaction methods is suggested. Sensitivity for hydrazine, acetylisoniazid was 0.1 mg%, for opianic and isonicotinic acids--0.05 mg%.     

An infant fatality involving ajmaline

An infant fatality following accidental ingestion of ajmaline is described. Ajmaline was determined by thin-layer chromatography and infrared spectrophotometry, and quantitated by high performance liquid chromatography. The ajmaline concentration in blood was 5.5 micrograms/mL. The toxicological data relevant to the interpretation of case findings are presented.     

生物样品中苯二氮卓类药物检验概述

概述了苯二氮卓类药物的种类、性质和生物样品中苯二氮卓类药物的提取净化及检验方法。提取净化方法包括液-液萃取法、固相萃取(SPE)、固相微萃取(SPME)。检验方法有免疫测定法、TLC、GC、HPLC、GC/MS等。     

Chemical-toxicological analysis of butorphanol

The conditions of butorphanol isolation from biological fluids were studied. The method of its extraction with the mix of organic solvents by pH 12 was proposed. How to identify butorphanol with the methods of thin-layer chromatography, ultraviolet spectrometry, high-performance liquid chromatography, gas chromatography with a detector of electron capture, chromato-mass spectrometry was developed. Possibility of use ultraviolet spectrometry for quantitative assessment of butorphanol was shown.     

Complex chemical and toxicological analysis of prosidol

Methods for measuring a Russian narcotic analgesic prosidol are suggested: thin-layer chromatography, microcrystalloscopy, gaseous chromatography with ionization flame detector, gas chromatography with mass selective detector, ultraviolet spectroscopy, high-performance liquid chromatography with ultraviolet detector, proton nuclear magnetic resonance used in chemical toxicological analysis, pharmacological analysis, and investigation of material evidence pieces.     

The detection of nifedipine in biological materials

The objective of the present study was to find optimal conditions for the isolation of nifedipine from biological materials by ethylacetate. It was shown that nifedipine can be purified from co-extracted substances of the biological material on a Silasorb C-18 column with the size of the particles 30 microns. The authors propose to use thin-layer chromatography, IR spectrophotometry, and reverse-phase high performance liquid chromatography for the identification and quantitative determination of nifedipine extracted from cadaveric liver samples.     

Detection of the cholinesterase inhibitor tacrine and its main metabolites

Tacrine, a cholinesterase inhibitor for symptomatic treatment of minor to moderate dementia, and its primary metabolites 1-hydroxy-tacrine and 4-hydroxy-tacrine were studied by means of thin-layer chromatography, UV spectroscopy and gas-chromatography/mass spectroscopy. The analytical data (corrected hRf values, UV spectra in solution as well as reflectance spectra, high-pressure liquid chromatography data, GC retention indices and EI mass spectra) including various derivatization methods are described.     

The detection of aromatic substances in biological material]

The author presents experimental data and suggests a method for extraction of aromatic substances from the blood, urine, lavage water, stomach and its contents, liver and kidneys. The extract is dissolved in 96% ethanol and the aromatic substances are detected in reactions with hydrochloric acid, Marki's reagent, 2,4-dinitrophenylhydrazine, diazotized o-dianisidine, phthivazide, chromotropic acid by UV spectrophotometry, thin-layer and gas-liquid chromatography. The sensitivity of the method is 0.1-0.5 mg %.     

Detection of bancol for the purpose of forensic chemical expertise

Optimal conditions for the extraction of bancol from the biological material with toluene are described. The possibility of its purification and separation from co-extracted compounds on a silicagel L column, 40/100 mcm is illustrated. Identification and quantitative determination of bancol isolated from the cadaverous liver were performed by the electron spectrophotometry technique, thin-layer chromatography, and high performance liquid chromatography using normal-phase sorbents. A method of bancol detection was adapted for the purpose of forensic medical expertise and applied for the postmortem examination of the cadaverous tissues.     

A rapid identification of black colour materials with specific reference to ballpoint ink and Indian ink

Seventy-four aqueous and oil-based black, ballpoint inks were examined by four methods: photography before and after exposure to visible and UV light; thin-layer chromatography followed by densitometry; visible light spectrophotometry; and X-ray microanalysis. Nine Indian inks were also examined using only X-ray microanalysis. The results showed that it is possible to identify the brand of black ink used in a criminal document, for most Japanese and foreign inks, by employing a combination of procedures.     

Simultaneous identification/determination system for phentolamine and sildenafil as adulterants in soft drinks advertising roborant nutrition

An easily available, simultaneous identification/determination procedure for phentolamine (PHE) and sildenafil (SIL) in adulterated dietary supplements was established by using a combination of three different analytical methods; thin-layer chromatography (TLC), liquid chromatography-mass spectrometry (LC/MS) and a high-performance liquid chromatography (HPLC)/photo-diode-array. The sample solution for TLC was applied to silica gel 60 F(254) plates with chloroform/ammonia solution (28)/methanol (70:5:3, lower layer) and chloroform/diethylamine/methanol (15:3:2) as the developing solvent. Spots were located under UV radiation at 254 nm. Mass spectra of PHE and SIL by LC/MS were investigated with electrospray ionization (ESI) interface, under both positive and negative ion mode. The HPLC analysis was performed on a column of Wakosil 5C18 (4.6 mm x 150 mm, 5 microm) with water/methanol/acetonitrile/triethylamine (580:250:170:1) adjusted with phosphoric acid to pH 3.0 as the mobile phase, and the effluent was monitored with a photo-diode-array detector. Quantitative HPLC analysis of PHE and SIL were detected at 280 nm. When this procedure was applied to commercial soft drinks, PHE and SIL were identified and determined at a concentration of 17 mg PHE and 44 mg SIL per bottle, respectively. The procedure described here is available for the screening of PHE and SIL in adulterated supplements.     

Characterization and dating of blue ballpoint pen inks using principal component analysis of UV-Vis absorption spectra, IR spectroscopy, and HPTLC

The ink of pens and ink extracted from lines on white photocopier paper of 10 blue ballpoint pens were subjected to ultraviolet-visible (UV-Vis) spectroscopy, infrared (IR), and high-performance thin-layer liquid chromatography (HPTLC). The R(f) values and color tones of the bands separated by thin-layer chromatography (TLC) analysis used to classify the writing inks into three groups. The principal component analysis (PCA) investigates the pen responsible for a piece of writing, and how time affects spectroscopy of written ink. PCA can differentiate between pen ink and ink line indicates the influence of solvent extraction process on the results. The PCA loadings are useful in individualization of a questioned ink from a database. The PCA of ink lines extracted at different times can be used to estimate the time at which a questioned document was written. The results proved that the UV-Vis spectra are effective tool to separate blue ballpoint pen ink in most cases rather than IR and HPTLC.     

Simultaneous identification/determination system for phentolamine and sildenafil as adulterants in soft drinks advertising roborant nutrition

An easily available, simultaneous identification/determination procedure for phentolamine (PHE) and sildenafil (SIL) in adulterated dietary supplements was established by using a combination of three different analytical methods; thin-layer chromatography (TLC), liquid chromatography–mass spectrometry (LC/MS) and a high-performance liquid chromatography (HPLC)/photo-diode-array. The sample solution for TLC was applied to silica gel 60 F₂₅₄ plates with chloroform/ammonia solution (28)/methanol (70:5:3, lower layer) and chloroform/diethylamine/methanol (15:3:2) as the developing solvent. Spots were located under UV radiation at 254 nm. Mass spectra of PHE and SIL by LC/MS were investigated with electrospray ionization (ESI) interface, under both positive and negative ion mode. The HPLC analysis was performed on a column of Wakosil 5C18 (4.6 mm×150 mm, 5 μm) with water/methanol/acetonitrile/triethylamine (580:250:170:1) adjusted with phosphoric acid to pH 3.0 as the mobile phase, and the effluent was monitored with a photo-diode-array detector. Quantitative HPLC analysis of PHE and SIL were detected at 280 nm. When this procedure was applied to commercial soft drinks, PHE and SIL were identified and determined at a concentration of 17 mg PHE and 44 mg SIL per bottle, respectively. The procedure described here is available for the screening of PHE and SIL in adulterated supplements.     

A diflunisal related fatality: a case report

A case is reported where the death of an individual resulted from the ingestion of diflunisal. Diflunisal was identified by a combination of liquid chromatography, UV spectrophotometry and colorimetry. Diflunisal was quantified in blood (260 mg/l), bile (71 mg/l), kidney (350 mg/kg), liver (400 mg/kg), stomach contents (34 mg) and urine (78 mg/l). No previous literature references discussing diflunisal related fatalities were available.     

Analysis of amphetamines by supercritical fluid chromatography,high-performance liquid chromatography,gas chromatography and capillary zone electrophoresis; a preliminary comparison

A supercritical fluid chromatographic method with UV detection (SFC–UV) for the quantitative separation of phenylisothiocyanate (PITC)-derivatised amphetamines is described and compared to high-performance liquid chromatography–diode array detection (HPLC–DAD), gas chromatography–flame ionisation detection (GC–FID) and capillary zone electrophoresis–diode array detection (CZE–DAD) analyses of amphetamine and related compounds. Difficulties in the analysis of common amphetamines by SFC are discussed. Of the methods described in this paper, the SFC method offered the greatest sensitivity at 0.01–0.02 μg of drug on column. Suggestions are made for the use of combinations of these techniques for the identification of amphetamines when gas chromatography–mass spectrometry is not available.     

The Characterization of 3,4-Dimethylmethcathinone (3,4-DMMC)

Analogs and derivatives of traditional illicit drugs are ever increasing in variety and creativity. Staying abreast of the new developments is a constant challenge for every forensic laboratory. Recently, a seizure from Australian Customs Service presented our laboratory with the designer cathinone 3,4-dimethylmethcathinone (3,4-DMMC). Gas chromatography/mass spectrometry (GC/MS), liquid chromatography/mass spectrometry (LC/MS), nuclear magnetic resonance (NMR) spectroscopy, infrared (IR) spectroscopy, and ultraviolet (UV) spectrophotometry were employed to analyze the spectroscopic characteristics of this cathinone. As an analog, 3,4-DMMC exhibits similar if not identical IR and UV profiles to mephedrone (4-MMC) and methcathinone; however, the retention time from GC is unique as expected, and the electron impact fragmentation pattern is consistent with the fragmentation pattern of other cathinones. The chemical shifts of the carbons and hydrogens were assigned by both one- and two-dimensional NMR techniques, while the molecular weight was confirmed by LC/MS.     

Comparative analysis of gamma-hydroxybutyrate and gamma-hydroxyvalerate using GC/MS and HPLC

This paper describes two analytical techniques used to separate and quantify gamma-hydroxybutyrate (GHB) and gamma-hydroxyvalerate (GHV). The first technique was a N,O-bis(trimethylsilyl)triflouro-acetimide-trimethylchlorosilane derivatization, followed by gas chromatography/mass spectrometry analysis using an HP-5 capillary column at a rate of 1.0 mL/min with a run time of 9.25 min. This technique was found to be sensitive (LOD 1 pg on column) and gave a low average error (5%) in a beverage study. When supplemented by a surrogate spike, the method yielded 97% analyte recovery from beverages. The second technique was high-performance liquid chromatography/UV (HPLC/UV) using a C-18 column with a (20:80% v/v) methanol:dibasic phosphoric buffer (10 mM, pH 3) at a rate of 1.00 mL/min with a run time of 7.5 min. UV detection occurred at 254 nm. This method was found to be less sensitive (LOD 0.05 microg on column) for direct analysis of aqueous samples. To remove interferences seen in the beverage study, a liquid-liquid extraction before HPLC analysis was tested. However, a decreased sensitivity (LOD 100 microg on column) and irreproducible peak profiles resulted.     

A quantitative densitometric determination of heroin and cocaine samples by high-performance thin-layer chromatography

The traditional thin-layer chromatography (TLC) is a sensitive technique frequently used in chemical analysis for semiquantitative determinations. In the last years a high-performance thin-layer chromatography system (HPTLC) has been developed. It assures quantitative determinations with direct densitometric measurements of chromatographic spots in situ on the plate. Here, we wish to report a method for the drug determination in street samples, that employs a CAMAG TLC/HPTLC Scanner Photodensitometer and a CAMAG LINOMAT III for sample application. Samples of illicit drug traffic (50 samples of street heroin and 30 samples of street cocaine) are tested and the gas-liquid chromatography (GLC) and HPTLC determinations are compared. The HPTLC method has proven to be sensitive, precise and accurate for quantitative determinations of drugs in street samples. Furthermore this method may be useful in forensic chemistry to show a "fingerprint" of each sample.     

Analysis of volatile compounds in heroin samples

Volatile compounds of 32 street heroin samples were analyzed by head space gas-chromatographic (HSGC) technique. The reliability of this procedure coupled with thin-layer chromatography (TLC), gas chromatography (GC), high performance liquid chromatography (HPLC), and its application to forensic casework (comparative sample analysis) is discussed.     

Chromophoric labeling of cannabinoids with 4-dimethylaminoazobenzene-4'-sulfonyl chloride

A simple and sensitive assay for the cannabinoids is presented using a dabsylation procedure. Dabsyl derivatives of delta 9-tetrahydrocannabinol (delta 9-THC) and cannabinol (CBN) were prepared by reacting with 4-dimethylaminoazobenzene-4'-sulfonyl chloride (dabsyl chloride) in acetone in the presence of sodium carbonate-sodium bicarbonate buffer (pH 10). Crystalline dabsylcannabinoids gave intense absorption in the visible region. With these derivatives, analysis by thin-layer chromatography (TLC) and high performance liquid chromatography (HPLC) were tested. These techniques gave good separation and nanogram detection of dabsyl-THC and -CBN by using n-hexane-ethyl acetate-diethylamine (20:5:1) for TLC and MeOH--H2O (95:5) at 450 nm for HPLC.