High-performance liquid chromatography-ultraviolet-visible spectroscopy-electrospray ionization mass spectrometry method for acrylic and polyester forensic fiber dye analysis

A critical point of comparison between a fiber collected from a crime scene and a fiber from a known source is the color. Fiber dye analysis using thin-layer chromatography or ultraviolet (UV)-visible (Vis) microspectrophotometry provides useful, although limited, data for comparison. High-performance liquid chromatography-electrospray ionization mass spectrometry (LC/MS) overcomes these limitations by integrating chromatography, ultraviolet-visible spectroscopy, and mass spectrometry into a single instrument. In order to evaluate the applicability of the LC/MS to forensic fiber dye analysis, a multi-stage chromatographic method using acidified water and acidified acetonitrile was developed that separated and identified a mixture of 15 basic and 13 disperse dye standards. The LC/MS also detected and analyzed dyes extracted from individual 0.5 cm acrylic and polyester fibers, demonstrating its applicability to this type of analysis. With regard to the analysis of disperse dyes in polyester fibers, the replacement of pyridine with acetonitrile in the extraction system allowed direct injection of the extracts into the LC/MS. The advantage of the LC/MS over other instrumental methods of textile dye analysis is demonstrated by the analysis and differentiation of three black acrylic fibers: two fibers had similar UV-Vis spectra but were differentiated with chromatography and two had similar UV-Vis spectra and chromatograms but were differentiated using the mass spectrometer.     

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.     

The Identification of Spiromesifen,a Recently Introduced Pesticide,Using Approaches to Chemical Unknown Analysis

An unknown, viscous, opaque, white liquid with a strong, unpleasant odor was submitted with a request for identification. It was analyzed using infrared (IR) spectroscopy, gas chromatography–mass spectrometry, and X‐ray fluorescence spectroscopy. It was found to contain glycerin as well as another compound. IR and mass spectral data were readily obtained for this second component, but it was not easily identified as common instrument libraries had no matching spectra. After an extensive literature search, the unknown compound was identified as spiromesifen, a recently introduced pesticide. The IR spectrum and electron impact mass spectrum of spiromesifen are presented here as these are not available in the published literature. This case report also provides useful approaches for searching for and identifying an unknown compound when it is not found in a laboratory's spectral libraries.     

An alternative method to screen for pepper spray residue

A method was developed to screen for pepper spray residue using instruments and methods other than those techniques commonly employed to analyze chemical residue (i.e.. gas chromatography mass spectrometry-GCMS or liquid chromatography mass spectrometry-LCMS). The method employed gas chromatography (GC), thin layer chromatography (TLC), and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) to screen for dried pepper spray stains. Pepper sprays from nine different manufacturers were investigated. Capsaicin and dihydrocapsaicin were identified and unique IR reflectance spectra are presented. An additional five compounds were presumptively found. Results showed that a particular stain could be characterized as a pepper-based stain.     

Discrimination of rubber-based pressure sensitive adhesives by size exclusion chromatography

In this report, three pairs of rubber-based pressure sensitive adhesives were analyzed by pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS), attenuated total reflectance Fourier transform infrared spectrometry (ATR/FT-IR) and size exclusion chromatography (SEC). The size exclusion chromatograph was equipped with a refractive index (RI) detector and an ultraviolet (UV) absorption detector set to measure at 254 nm. Both adhesives of each pair revealed indistinguishable pyrograms and IR spectra, however, the SEC chromatograms were able to provide further discrimination. The differences were observed in the range below the polystyrene equivalent molecular weight of 700 Da.     

Quick Screening of Crystal Methamphetamine/Methyl Sulfone Exhibits by Raman Spectroscopy

Abstract: The analysis of mixtures of “crystal meth” (usually comprised of methyl sulfone [MS] and methamphetamine [MA]) by gas chromatography‐mass spectrometry (GCMS) is routine in many forensic drug laboratories. The utilization of Raman spectroscopy for the identification of such mixtures quickly and without the need for a separation technique is discussed. Samples were dissolved in water and Raman spectra of the resulting aqueous solutions were collected. By comparing these spectra to spectra of methylsulfone and MA mixtures of known composition, an indication of the composition of the sample can be obtained in only a few minutes. This spectral comparison also can be used as a semi‐quantitative analysis of MA concentrations in such exhibits.     

The analysis and identification of steroids.

In October 1987, anabolic steroids were controlled under Schedule IV of Florida State Statute 893. This study was designed to establish a method of analysis and identification of evidentiary cases. Spot tests, Fourier transform infrared spectroscopy (FT-IR), gas chromatography/mass spectroscopy (GC/MS), Fourier transform nuclear magnetic resonance (FT-NMR), thin-layer chromatography (TLC), and extractions were performed on standard and pharmaceutical steroids. Mandelin's accompanied by the sulfuric acid test was found to provide the best indication of a steroid among the following four spot tests performed: sulfuric acid, napthol-sulfuric acid, Liebermann's, and Mandelin's. TLC was successfully performed on the steroid samples using two different eluent systems: TP and TQ. GC/MS was a very useful method of analysis applicable to most steroids, with only a few exceptions. FT-IR spectra were found to match the spectra from the literature for all the standards tested. The combination of the above techniques was used successfully to identify all the standards tested.     

On the challenge of unambiguous identification of fentanyl analogs: Exploring measurement diversity using standard reference mass spectral libraries

Fentanyl analogs are a class of designer drugs that are particularly challenging to unambiguously identify due to the mass spectral and retention time similarities of unique compounds. In this paper, we use agglomerative hierarchical clustering to explore the measurement diversity of fentanyl analogs and better understand the challenge of unambiguous identifications using analytical techniques traditionally available to drug chemists. We consider four measurements in particular: gas chromatography retention indices, electron ionization mass spectra, electrospray ionization tandem mass spectra, and direct analysis in real time mass spectra. Our analysis demonstrates how simultaneously considering data from multiple measurement techniques increases the observable measurement diversity of fentanyl analogs, which can reduce identification ambiguity. This paper further supports the use of multiple analytical techniques to identify fentanyl analogs (among other substances), as is recommended by the Scientific Working Group for the Analysis of Seized Drugs (SWGDRUG).     

Analytical characterization of isoheroin

The synthesis of isoheroin is presented with the analytical data (mass spectroscopy [MS], nuclear magnetic resonance [NMR], infrared spectroscopy [IR], and gas liquid chromatography [GLC]) for this compound. Comparison between analytical results for heroin and isoheroin shows differentiation is possible.     

The Analysis of Colored Acrylic,Cotton, and Wool Textile Fibers Using Micro‐Raman Spectroscopy. Part 2: Comparison with the Traditional Methods of Fiber Examination

In the second part of this survey, the ability of micro‐Raman spectroscopy to discriminate 180 fiber samples of blue, black, and red cottons, wools, and acrylics was compared to that gathered with the traditional methods for the examination of textile fibers in a forensic context (including light microscopy methods, UV‐vis microspectrophotometry and thin‐layer chromatography). This study shows that the Raman technique plays a complementary and useful role to obtain further discriminations after the application of light microscopy methods and UV‐vis microspectrophotometry and assure the nondestructive nature of the analytical sequence. These additional discriminations were observed despite the lower discriminating powers of Raman data considered individually, compared to those of light microscopy and UV‐vis MSP. This study also confirms that an instrument equipped with several laser lines is necessary for an efficient use as applied to the examination of textile fibers in a forensic setting.     

Microcrystalline identification of drugs of abuse: the psychedelic amphetamines

The optical crystallographic or microcrystalline properties of the diliturate derivatives (5-nitrobarbituric acid) of the most used psychedelic amphetamine drugs have been determined. The crystallographic properties, especially the orthographic projection drawings and photomicrography of the crystals and other optical crystallographic data, such as the indices of refraction, extinction angles, and optical orientations serve to characterize and identify this group of drug chemicals. These data can be used with ultraviolet-infrared (UV-IR) spectroscopy, thin-layer chromatography and gas-liquid chromatography/mass spectrometry (GLC/MS) data for the identification and confirmation of psychedelic amphetamine drugs.     

Differentiation of methylenedioxybenzylpiperazines (MDBPs) and methoxymethylbenzylpiperazines (MMBPs) By GC-IRD and GC-MS

The substituted benzylpiperazines, 3,4-methylenedioxybenzylpiperazine (3,4-MDBP), its regioisomer 2,3-methylenedioxybenzylpiperazine (2,3-MDBP) and four isobaric ring substituted methoxymethylbenzylpiperazines (MMBP) have almost identical mass spectra. Perfluoroacylation of the secondary amine nitrogen of these isomeric piperazines gave mass spectra with differences in relative abundance of some fragment ions. However, the spectra did not yield any unique fragments for specific identification of one isomer to the exclusion of the other compounds. Gas chromatography coupled with infrared detection (GC-IRD) provides direct confirmatory data for the structural differentiation between the six isomers. The mass spectra in combination with the vapor phase infrared spectra provide for specific confirmation of each of the isomeric piperazines. The underivatized and perfluoroacyl derivative forms of the ring substituted benzylpiperazines were resolved on the polar stationary phase Rtx-200.     

The application of chromatography and spectrometry for the analysis of ketorolac and diclofenac in biological fluids

The objective of the present work was to study conditions for isolation of ketorolac and diclofenac from biological fluids. A method of their extraction with a mixture of organic solvents has been developed and the conditions for the identification of these compounds are proposed with the use of high performance liquid chromatography (HPLC), UV spectroscopy, and gas chromatography with electron capture detection (GC/ECD). The possibilities of using HPLC, UV spectrometry, and GC/ECD for quantitative determination of ketorolac and diclofenac are illustrated.     

Synthetic cannabinoids in "spice-like" herbal blends: First appearance of JWH-307 and recurrence of JWH-018 on the German market

Herbal smoking blends, available on the German market were analyzed and several known synthetic cannabinoids were identified (JWH-122 and JWH-018). In addition, we isolated a new active ingredient by silica gel column chromatography and elucidated the structure by nuclear magnetic resonance (NMR) methods. The compound was identified as JWH-307, a synthetic cannabinoid of the phenyl-pyrrole subclass with known in vitro binding affinities for cannabinoid receptors. To date, this is the first appearance of this subclass of cannabimimetics in such products. JWH-307 has been further characterized by gas chromatography accurate mass spectrometry (GC-HRMS), electrospray tandem mass spectrometry (ESI-MS/MS), ultraviolet (UV) and infrared (IR) spectroscopy. JWH-018 was among the first compounds banned by many countries world-wide including Germany. The identification of JWH-018 was striking, since this is the first report where JWH-018 recurred on the German market thus violating existing laws. A generic method was established to quantify synthetic cannabinoids in herbal smoking blends. Quantification was achieved using an isotopically labeled standard (JWH-018-D(3)). JWH-018 was found at a level of 150mg/g while JWH-122 and JWH-307 occurred as a mixture at a total level of 232mg/g.     

Hierarchical Cluster Analysis of Ignitable Liquids Based on the Total Ion Spectrum

Gas chromatography–mass spectrometry (GC–MS) data of ignitable liquids in the Ignitable Liquids Reference Collection (ILRC) database were processed to obtain 445 total ion spectra (TIS), that is, average mass spectra across the chromatographic profile. Hierarchical cluster analysis, an unsupervised learning technique, was applied to find features useful for classification of ignitable liquids. A combination of the correlation distance and average linkage was utilized for grouping ignitable liquids with similar chemical composition. This study evaluated whether hierarchical cluster analysis of the TIS would cluster together ignitable liquids of the same ASTM class assignment, as designated in the ILRC database. The ignitable liquids clustered based on their chemical composition, and the ignitable liquids within each cluster were predominantly from one ASTM E1618‐11 class. These results reinforce use of the TIS as a tool to aid in forensic fire debris analysis.     

Identification of 1-butyl-3-(1-(4-methyl)naphthoyl)indole in a herbal mixture

Besides the cannabinoid mimetic JWH-073, a novel 4 methylnaphthoyl homologue of JWH-073 was detected in a herbal mixture. The structure of the compound was elucidated after thin layer chromatographic enrichment from the herbal mixture by nuclear magnetic resonance (NMR) and gas chromatographic mass spectrometric (GC-MS) analysis. The paper outlines data after GC-MS, liquid chromatography mass spectrometry (LC-MS) and NMR spectroscopy, and describes the structure elucidation.     

1H NMR spectroscopic identification of a glue sniffing biomarker

Organic solvent abuse typically involves sniffing organic solvents to experience the mind-altering conditions they induce. In Republic of Korea, organic solvent abuse is a serious social problem, especially among teenagers. Several studies have addressed the effects of organic solvent abuse on mind and body, but there are no simple methods by which such abuse can be positively identified. In this report, we describe a method for analyzing toluene metabolites (toluene is the main ingredient of glue) in glue-sniffers' urine using (1)H NMR spectroscopy. Toluene is a commonly used solvent in the rubber, paint, plastics, leather, printing, and chemical industries. Inhaled toluene is metabolized to hippuric acid in the liver and excreted in the urine. Hippuric acid is known as a good biomarker for biological monitoring of toluene exposure. We have scanned hippuric acid and other toluene metabolites by NMR spectroscopy and performed statistical multivariate analysis of the data. Based on this analysis, we sought to determine parameters by which glue-sniffing (toluene inhalation) behavior may be verified. We also demonstrate the use of a pattern recognition method for accurate and efficient analysis of NMR data. In comparison to conventional methods, such as mass spectroscopy coupled with liquid chromatography or gas chromatography, nuclear magnetic resonance spectroscopy has several advantages, including simple sample preparation, non-destructive sampling, accuracy, short acquisition time, and reproducibility in the determination of urinary hippuric acid.     

Fatal combined anileridine-pethidine poisoning. A gas chromatography, thin layer chromatography and mass spectrometry investigation.

Anileridine and pethidine were established by gas and thin layer chromatography and mass spectroscopy. In the mass spectrum the main peak of anileridine is found at m/e 246 and that of pethidine at m/e 71. The determination was made by gas chromatography from the blood, urine, liver, muscle and stomach contents.     

紫外可见漫反射光谱法无损确证血痕的研究

目的建立一种快速确定血痕的方法。方法将人血、猪血、鸡血、羊血等制成样品纱布,利用紫外可见分光光度计扫描反射光谱进行检测,同时考察了人血的最低检出量。结果血痕的种属与浓度不影响紫外可见反射光谱波峰波谷位置;人血的最低检出量为1.0μL。结论该方法确证血痕具有快速、灵敏、准确、不损坏检材的特点。     

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.