Rapid Identification of Synthetic Cannabinoids in Herbal Incenses with DART‐MS and NMR

The usage of herbal incenses containing synthetic cannabinoids has caused an increase in medical incidents and triggered legislations to ban these products throughout the world. Law enforcement agencies are experiencing sample backlogs due to the variety of the products and the addition of new and still‐legal compounds. In our study, proton nuclear magnetic resonance (NMR) spectroscopy was employed to promptly screen the synthetic cannabinoids after their rapid, direct detection on the herbs and in the powders by direct analysis in real time mass spectrometry (DART‐MS). A simple sample preparation protocol was employed on 50 mg of herbal sample matrices for quick NMR detection. Ten synthetic cannabinoids were discovered in fifteen herbal incenses. The combined DART‐MS and NMR methods can be used to quickly screen synthetic cannabinoids in powder and herbal samples, serving as a complementary approach to conventional GC‐MS or LC‐MS methods.     

Identification of 2‐(ethylamino)‐1‐(4‐methylphenyl)‐1‐pentanone (4‐MEAP), a New “Legal High” Sold by an Internet Vendor as 4‐Methyl Pentedrone

Online vendors are offering a new legal high, 4‐methylpentedrone (4‐MPD). Information for potential users provided by internet vendors of 4‐MPD includes incorrect structures and nonexistent CAS numbers. A sample of 4‐MPD was obtained and analyzed using GC‐MS, NMR, and LC‐EIS. The fragmentation data from the GC‐MS and LC‐EIS produced an M‐1 ion that suggested the molecular mass was 219 amu, rather than 205 amu as calculated for 4‐methylpentedrone. The difference in molecular mass corresponded to the addition of a methyl group. Based on the mass and fragmentation pattern, two standards were synthesized, 2‐(ethylamino)‐1‐(4‐methylphenyl)‐1‐pentanone and 1‐(4‐methylphenyl)‐2‐(propylamino)‐1‐butanone. The synthesis involved bromination of the appropriate ketone followed by the reaction with ethylamine or propylamine. Based on the NMR data and unique fragmentation patterns produced by these molecules, the sample was identified as 2‐(ethylamino)‐1‐(4‐methylphenyl)‐1‐pentanone, not 4‐methylpentedrone.     

Forensic Discrimination of Dyed Hair Color: II. Multivariate Statistical Analysis*,†

Abstract: This research is intended to assess the ability of UV–visible microspectrophotometry to successfully discriminate the color of dyed hair. Fifty‐five red hair dyes were analyzed and evaluated using multivariate statistical techniques including agglomerative hierarchical clustering (AHC), principal component analysis (PCA), and discriminant analysis (DA). The spectra were grouped into three classes, which were visually consistent with different shades of red. A two‐dimensional PCA observations plot was constructed, describing 78.6% of the overall variance. The wavelength regions associated with the absorbance of hair and dye were highly correlated. Principal components were selected to represent 95% of the overall variance for analysis with DA. A classification accuracy of 89% was observed for the comprehensive dye set, while external validation using 20 of the dyes resulted in a prediction accuracy of 75%. Significant color loss from successive washing of hair samples was estimated to occur within 3 weeks of dye application.     

Identification of 1‐(2,3‐dihydro‐1H‐inden‐5‐yl)‐2‐(ethylamino)pentan‐1‐one (bk‐IVP) in a Seized Drug Exhibit

To circumvent the law by evading regulation and obscuring their identities in routine analyses, numerous substituted cathinones have entered the illicit drug market. These compounds have been coined “bath salts” by users. In the described case, the laboratory received an unknown white powder for controlled substances identification. The sample could not be immediately identified using standard methods and procedures. Ultimately, the structure was elucidated using GC‐MS, NMR, FTIR, GC‐SPIR, UV, and color tests to be 1‐(2,3‐dihydro‐1H‐inden‐5‐yl)‐2‐(ethylamino)pentan‐1‐one (bk‐IVP), a cathinone analog with a rarely observed nonoxygenated bicyclic ring system. Features of spectra and chemical tests are reported that distinguish this class of cathinones from heterocyclic analogs.     

利用多体素氢质子磁共振波谱推测死亡时间

目的利用多体素氢质子磁共振波谱推断死亡时间。方法选取12只白兔,利用多体素磁共振波谱测定死后0.5、1、2、4、6、8、12、16、24h脑内N-乙酰天冬氨酸、胆碱复合物及磷酸肌酸和肌酸的代谢值。结果在死后24h内Naa/Cr、Naa/Ch随死亡时间的延长而降低;Ch/Cr先升高再下降,然后持续升高。结论经多体素质子磁共振研究,Naa/Cr、Naa/Ch、Ch/Cr死后改变呈现一定规律,可用于推断死亡时间。     

Optimizing Accu Time‐of‐Flight/Direct Analysis in Real Time for Explosive Residue Analysis

The use of a direct analysis in real time (DART) mass spectrometer (MS) instrument was optimized for 22 compounds of organic explosive residues to provide a guide for DART‐MS users in rapid screening of explosive compounds. Samples were introduced as neat solutions and sequential dilutions to determine optimal instrument conditions and lowest concentration detectable. Most compounds were optimized to 250°C in the negative ion mode, and several compounds benefited from the addition of a chloride dopant from methylene chloride (amino‐dinitrotoluenes, RDX, EGDN, and PETN). Few compounds were more sensitive in the positive ion mode (TEGDN, DEGDN, HNS, and DMNB). Mixtures of compounds were detected using clean room wipes, directly from their surfaces and from subsequent extractions. Compounds from the mixtures were also successfully detected in soil and from swipes of spiked surfaces. The instrument showed merit in detection of pg/μL solutions for most of the compounds and among the substrates tested.     

Characterization and Differentiation of Geometric Isomers of 3‐methylfentanyl Analogs by Gas Chromatography/Mass Spectrometry,Liquid Chromatography/Mass Spectrometry,and Nuclear Magnetic Resonance Spectroscopy

The cis and trans isomers of 3‐methylfentanyl and its three analogs were chemically synthesized, and these compounds were characterized and differentiated by gas chromatography/mass spectrometry (GC/MS), liquid chromatography/mass spectrometry (LC/MS), and nuclear magnetic resonance (NMR) spectroscopy. The cis and trans isomers of the 3‐methylfentanyl analogs were completely separated by GC/MS. Although the high temperature of the GC injection port caused thermal degradation of β‐hydroxy‐3‐methylfentanyl, the degradation was completely suppressed by trimethylsilyl derivatization. The isomers were also well separated by LC/MS on an octadecylsilyl column with 10 mM ammonium acetate and methanol as the mobile phase. The proton NMR signals were split when the hydrochloride salts of the 3‐methylfentanyl analogs were dissolved in deuterated chloroform because stereoisomers were formed by the coordination of the hydrochloride proton to the nitrogen of the piperidine ring of the 3‐methylfentanyl analogs.     

A Large‐Sample Test of a Semi‐Automated Clavicle Search Engine to Assist Skeletal Identification by Radiograph Comparison

In 2014, a morphometric capability to search chest radiograph databases by quantified clavicle shape was published to assist skeletal identification. Here, we extend the validation tests conducted by increasing the search universe 18‐fold, from 409 to 7361 individuals to determine whether there is any associated decrease in performance under these more challenging circumstances. The number of trials and analysts were also increased, respectively, from 17 to 30 skeletons, and two to four examiners. Elliptical Fourier analysis was conducted on clavicles from each skeleton by each analyst (shadowgrams trimmed from scratch in every instance) and compared to the search universe. Correctly matching individuals were found in shortlists of 10% of the sample 70% of the time. This rate is similar to, although slightly lower than, rates previously found for much smaller samples (80%). Accuracy and reliability are thereby maintained, even when the comparison system is challenged by much larger search universes.     

Elemental analysis of human cremains using ICP-OES to classify legitimate and contaminated cremains

The Tri-State Crematory Incident in Nobel, GA (February 2001) revealed limitations in traditional human cremated remains (cremains) analytical methodology. The goal of this study was to develop a method for effectively classifying questionable sets of cremains as legitimate or contaminated. Eighty-eight samples of known human cremains, concrete, mixtures of the two, and questionable sets of cremains were acid digested and analyzed for 21 elements by Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES). Variable cluster and principle component analyses identified the seven elements (Sb, B, Li, Mn, Sr, Tl, and V) used to develop discriminant functions to classify questionable sets into two groups: cremains and concrete. The discriminant analysis shows that at the 0.90 probability level, mixtures of 50% or less human content were classified as concrete. Mixtures with 90% human content classified as cremains. Sixty percent and 75% human content mixtures remained in the questionable classification, but as the concentration of human increased in the mixture, the probability of assignment to the known cremains group increased. Most of the questionable human samples classified as cremains. This is a pilot study and cannot yet satisfy Daubert standards for courtroom admissibility, but it indicates that it is possible to determine the legitimacy of cremains using elemental analysis by ICP-OES coupled with multivariate statistical analysis.     

Elemental Analysis of Variably Contaminated Cremains Using X‐ray Fluorescence Spectrometry

Analyzing and identifying skeletal remains becomes increasingly difficult when remains have been cremated, especially in cases where the cremated material may have been intentionally contaminated with nonskeletal material. This study examined the potential of X‐ray fluorescence spectrometry (XRF) to detect the presence of nonskeletal contaminants in samples of cremains. Eleven samples of cremains were variably combined with concrete mix and analyzed using XRF. Photon counts of elements in each sample were analyzed, and the coefficient of determination (R²) using unweighted linear regression as a function of percent cremains was calculated. Results showed that with changes in the proportion of skeletal material and contaminant, there were significant (R² > 0.90) changes in detected levels of phosphorus, potassium, zinc, aluminum, and sulfur. The use of XRF is concluded to be a valid approach in the identification of the presence of nonskeletal material in potentially contaminated cremains.     

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.     

Comparative Forensic Soil Analysis of New Jersey State Parks Using a Combination of Simple Techniques with Multivariate Statistics,

This study has shown that the combination of simple techniques with the use of multivariate statistics offers the potential for the comparative analysis of soil samples. Five samples were obtained from each of twelve state parks across New Jersey in both the summer and fall seasons. Each sample was examined using particle‐size distribution, pH analysis in both water and 1 M CaCl₂, and a loss on ignition technique. Data from each of the techniques were combined, and principal component analysis (PCA) and canonical discriminant analysis (CDA) were used for multivariate data transformation. Samples from different locations could be visually differentiated from one another using these multivariate plots. Hold‐one‐out cross‐validation analysis showed error rates as low as 3.33%. Ten blind study samples were analyzed resulting in no misclassifications using Mahalanobis distance calculations and visual examinations of multivariate plots. Seasonal variation was minimal between corresponding samples, suggesting potential success in forensic applications.     

Analysis of carbohydrates in seized heroin using capillary electrophoresis

Illicitly produced heroin is commonly cut with carbohydrates to increase bulk. The analysis of these solutes is important for legal and intelligence purposes. A capillary electrophoresis (CE) method was developed for the qualitative analysis of dextrose, lactose, sucrose, inositol, and mannitol in heroin exhibits. For this method, a 64 cm (55.5 cm to detector window) by 50 mum capillary was used with the Agilent Basic Anion Buffer modified to pH 12.1. This separation was performed at 25 degrees C with a voltage of 20 kV and indirect detection with 2,6-pyridinedicarboxylic acid as the visualization reagent. The methodology is also applicable for the screening of inorganic and organic anions using indirect detection, and acidic adulterants using direct detection. For a run time of 13 min, the relative standard deviation (n = 6) of the methodology was better than 0.36% for migration times and less than 2.6% for corrected peak areas. For the analysis of carbohydrates and acidic adulterants in seized heroin, excellent agreement was obtained between CE and nuclear magnetic resonance spectroscopy.     

Infrared Spectra of U.S. Automobile Original Finishes (Post – 1989). VIII: In Situ Identification of Bismuth Vanadate Using Extended Range FT‐IR Spectroscopy,Raman Spectroscopy,and X‐Ray Fluorescence Spectrometry

Chrome Yellow (PbCrO₄·xPbSO₄) was a common pigment in U.S. automobile OEM finishes for more than three decades, but in the early 1990s its use was discontinued. One of its main replacements was Bismuth Vanadate (BiVO₄·nBi₂MoO₆, n = 0–2), which was commercially introduced in 1985, as this inorganic pigment also produces a very bright hue and has excellent outdoor durability. This paper describes the in situ identification of Bismuth Vanadate in automotive finishes using FT‐IR and dispersive Raman spectroscopy and XRF spectrometry. Some differentiation of commercial formulations of this pigment is possible based on far‐infrared absorptions, Raman data, and elemental analysis. The spectral differences arise from the presence or absence of molybdenum, the use of two crystal polymorphs of BiVO₄, and differences in pigment stabilizers. Bismuth Vanadate is usually not used alone, and it is typically found with Isoindoline Yellow, hydrous ferric oxide, rutile, Isoindolinone Yellow 3R, or various combinations of these.     

Root Morphology and Anatomical Patterns in Forensic Dental Identification: A Comparison of Computer‐Aided Identification with Traditional Forensic Dental Identification*

Abstract: An online forensic dental identification exercise was conducted involving 24 antemortem–postmortem (AM–PM) dental radiograph pairs from actual forensic identification cases. Images had been digitally cropped to remove coronal tooth structure and dental restorations. Volunteer forensic odontologists were passively recruited to compare the AM–PM dental radiographs online and conclude identification status using the guidelines for identification from the American Board of Forensic Odontology. The mean accuracy rate for identification was 86.0% (standard deviation 9.2%). The same radiograph pairs were compared using a digital imaging software algorithm, which generated a normalized coefficient of similarity for each pair. Twenty of the radiograph pairs generated a mean accuracy of 85.0%. Four of the pairs could not be used to generate a coefficient of similarity. Receiver operator curve and area under the curve statistical analysis confirmed good discrimination abilities of both methods (online exercise = 0.978; UT‐ID index = 0.923) and Spearman’s rank correlation coefficient analysis (0.683) indicated good correlation between the results of both methods. Computer‐aided dental identification allows for an objective comparison of AM–PM radiographs and can be a useful tool to support a forensic dental identification conclusion.     

Specificity,Sensitivity, and Operability of RSID™‐Urine for Forensic Identification of Urine: Comparison with ELISA for Tamm‐Horsfall Protein

Abstract: In this study, the specificity, sensitivity, and operability of RSID?‐Urine, a new immunochromatographic test for urine identification, was evaluated and compared with ELISA detection of Tamm‐Horsfall protein (THP). Urine was successfully identified among other body fluids using RSID?‐Urine and ELISA detection of THP. The detection limit of RSID?‐Urine equated to 0.5 μL of urine; although the sensitivity of RSID?‐Urine may be lower than that of ELISA detection of THP, it is thought to be sufficient for application to casework samples. However, results from RSID?‐Urine must be interpreted with caution when the sample may have been contaminated with blood or vaginal fluid, because this might inhibit urine detection. The RSID?‐Urine assay can be performed in just 15 min by dropping the extracted sample onto the test cassette. Therefore, RSID?‐Urine should be an effective tool for the forensic identification of urine, in addition to ELISA detection of THP.     

The Accuracy of Handheld Pre‐Arrest Breath Test Instruments as a Predictor of the Evidential Breath Alcohol Test Results

Drunk driving is a serious threat to public safety. All available and appropriate tools for curbing this threat should be employed to their full extent. The handheld pre‐arrest breath test instrument (PBT) is one tool for identifying the alcohol‐impaired driver and enforcing drunk driving legislation. A set of data was evaluated (n = 1779) where the PBT instrument was employed in drunk driving arrests to develop a multivariate predictive model. When maintained and operated by trained personnel, the PBT provides a reasonable estimate of the evidential test result within the relevant forensic range (95% prediction interval:  ± 0.003 g/210 L). ROC analysis shows that a multivariate model for PBT prediction of the evidentiary alcohol concentration above versus below the legal limit of 0.08 g/210 L has excellent performance with an AUC of 0.96. These results would be of value in evidential hearings seeking to admit the PBT results in drunk driving trials.     

Determination of Acetamiprid and IM‐1‐2 in PostMortem Human Blood,Liver, Stomach Contents by HPLC‐DAD

An HPLC‐DAD method was developed to detect and quantify a neonicotinoid insecticide acetamiprid (ATP) and its metabolite IM‐1‐2 in autopsy samples of a fatal intoxication case. The postmortem blood and tissue distribution of ATP and IM‐1‐2 was determined for the first time. The method showed acceptable precisions and recoveries with relative standard deviations of <10% for ATP level and 1.38 % for IM‐1‐2. The detection and quantification limits for ATP were 0.015 μg/mL and 0.030 μg/mL for blood and were 0.035 μg/g and 0.050 μg/g for liver samples, respectively. The mean contents of ATP were 0.79 μg/g in the liver, 47.35 μg/g in the stomach contents and 2.7 μg/mL in the blood. IM‐1‐2 content was 17.0 μg/g in the stomach contents. ATP and IM‐1‐2 were not detected in the urine. The presence of ATP and IM‐1‐2 in the samples was confirmed by GC‐MS. The method can be exploited in future forensic casework.