Separation and Detection of Smokeless Powder Additives by Ultra Performance Liquid Chromatography with Tandem Mass Spectrometry (UPLC/MS/MS),

A reversed phase gradient ultra performance liquid chromatography tandem mass spectrometry (UPLC/MS/MS) method has been developed for the analysis of smokeless powders. A total of 20 different components were separated by UPLC and detected by MS/MS in multiple reaction monitoring (MRM) mode. These compounds included diphenylamines, centralites, nitrotoluenes, nitroglycerin, and various phthalates. Simultaneous positive and negative electrospray ionization (ESI) was used along with negative atmospheric pressure chemical ionization (APCI) to detect all compounds in a single analysis. Analysis times were under 8 min with a gradient of 10–73% organic at a flow rate of 0.500 mL/min. With this method, ultraviolet and MRM limits of detection ranging from 0.08 to 2.6 ng and 0.4–64 ng injected were achieved. Commercially available smokeless powders were also extracted with methylene chloride and characterized using the developed UPLC/MS/MS method. The procedure permits the determination of compositional differences between different brands as well as lot‐to‐lot variations.     

Analysis of Ecstasy Tablets Using Capillary Electrophoresis with Capacitively Coupled Contactless Conductivity Detection

A method for the identification of 3,4‐methylenedioxymethamphetamine (MDMA) and meta‐chlorophenylpiperazine (mCPP) was developed employing capillary electrophoresis (CE) with capacitively coupled contactless conductivity detection (C⁴D). Sample extraction, separation, and detection of “Ecstasy” tablets were performed in <10 min without sample derivatization. The separation electrolyte was 20 mm TAPS/Lithium, pH 8.7. Average minimal detectable amounts for MDMA and mCPP were 0.04 mg/tablet, several orders of magnitude lower than the minimum amount encountered in a tablet. Seven different Ecstasy tablets seized in Rio de Janeiro, Brazil, were analyzed by CE‐C⁴D and compared against routine gas chromatography‐mass spectrometry (GC‐MS). The CE method demonstrated sufficient selectivity to discriminate the two target drugs, MDMA and mCPP, from the other drugs present in seizures, namely amphepramone, fenproporex, caffeine, lidocaine, and cocaine. Separation was performed in <90 sec. The advantages of using C⁴D instead of traditional CE‐UV methods for in‐field analysis are also discussed.     

Determination of Nitrite in Whole Blood by High‐Performance Liquid Chromatography with Electrochemical Detection and a Case of Nitrite Poisoning

Although nitrite is widely used in meat processing, it is a major toxicity hazard to children and is responsible for the blue‐baby syndrome. A simple and effective method to determine nitrite in whole blood has been devised using ion chromatography with suppressed conductivity detection. The blood sample was deproteinized by adding acetonitrile and purified with mini‐cartridges to remove hydrophobic compounds, chloride ions, and metal ions. An aliquot of the filtrate was injected onto the ion chromatography. The retention time for nitrite was 13.8 min and the detection limit of nitrite in whole blood was 0.4 μmol/L. The calibration curve was linear (r² = 0.9999) over the concentration working range. The blood nitrite concentration of a victim who attempted suicide by ingesting sodium nitrite powder was determined using the present method. The basal levels for nitrite in human blood was determined with 7.1 ± 0.9 μmol/L (n = 12).     

A Direct Aqueous Derivatization GSMS Method for Determining Benzoylecgonine Concentrations in Human Urine

A sensitive and reliable method for extraction and quantification of benzoylecgonine (BZE) and cocaine (COC) in urine is presented. Propyl‐chloroformate was used as derivatizing agent, and it was directly added to the urine sample: the propyl derivative and COC were then recovered by liquid–liquid extraction procedure. Gas chromatography–mass spectrometry was used to detect the analytes in selected ion monitoring mode. The method proved to be precise for BZE and COC both in term of intraday and interday analysis, with a coefficient of variation (CV) <6%. Limits of detection (LOD) were 2.7 ng/mL for BZE and 1.4 ng/mL for COC. The calibration curve showed a linear relationship for BZE and COC (r² >0.999 and >0.997, respectively) within the range investigated. The method, applied to thirty authentic samples, showed to be very simple, fast, and reliable, so it can be easily applied in routine analysis for the quantification of BZE and COC in urine samples.     

Gender Determination of Adult Individuals by Three‐Dimensional Modeling of Canines

Gender determination is a fundamental issue in forensic anthropology. Many techniques based on bone and dental remains have been proposed. It is not always possible to implement the techniques using bones, but teeth are often perfectly preserved. It has been demonstrated that the canine has the greatest sexual dimorphism, and the aim of this work was to provide an easy and accurate dental technique for determining the gender in the absence of other skeletal elements. The sample was composed of 210 CT scans with four healthy canines. The 840 canines were modeled using MIMICS^® 10.01 software. The total volume of each tooth was determined. Seven mathematical models were determined by binary logistic regressions and ranked in order of relative performance. The seven proposed predictive models thus performed (0.910 ≤ AUC ≤ 0.938), with overall rates of correct predictions between 82.38 and 85.24%. The 4‐canine model is the most powerful for predicting the gender.     

Nitrate and Nitrite Determination in Gunshot Residue Samples by Capillary Electrophoresis in Acidic Run Buffer,

Simultaneous determination of nitrate and nitrite in gunshot residue has been conducted by capillary electrophoresis using an acidic run buffer (pH 3.5). In previously developed capillary electrophoretic methods, alkaline pH separation buffers were used where nitrite and nitrate possess similar electrophoretic mobility. In this study, the electroosmotic flow has been reversed by using low pH running buffer without any additives. As a result of reversing the electroosmotic flow, very fast analysis has been actualized, well‐defined and separated ion peaks emerge in less than 4 min. Besides, the limit of detection was improved by employing large volume sample stacking. Limit of detection values were 6.7 and 4.3 μM for nitrate and nitrite, respectively. In traditional procedure, mechanical agitation is employed for extraction, while in this work the extraction efficiency of ultrasound mixing for 30 min was found sufficient. The proposed method was successfully applied to authentic gunshot residue samples.     

Α Simple Method for the Determination of Lacosamide in Blood by GC-MS

Lacosamide is a functionalized amino acid with antiepileptic function. Therapeutic drug monitoring (TDM) in patients for lacosamide is critical as it allows clinicians to control epileptic seizures. A single liquid–liquid extraction step was applied for the extraction of lacosamide from whole blood samples which were thereafter analyzed by GC-MS. Optimum extraction conditions were selected on the basis of experiments with various solvents at different pHs, indicating ethyl acetate at pH 12 as the most efficient parameters for the extraction of lacosamide. Method exhibited linearity from 2 to 100 μg/mL with R² = 0.998. Accuracy and precision were evaluated at three concentrations and found to be within acceptable limits. LOD and LOQ were determined at 0.1 and 0.5 μg/mL, respectively. Lacosamide was found to be stable at storage conditions. The developed method was applied successfully in clinical samples and postmortem blood sample from an overdose case.     

A Comparison of Solvent Extract Cleanup Procedures in the Analysis of Organic Explosives

The use of an organic solvent to extract explosive residues from hand swabs and postblast debris inevitably leads to the coextraction of unwanted materials, usually in far greater quantities than any explosive residue. In this study, the extraction efficiency of a number of solvent cleanup procedures including solid‐phase extraction (SPE), adsorbent resins such as Chromosorb‐104, and traditional materials such as silica and Florisil was calculated using a quantitative liquid chromatography–ultraviolet (LC‐UV) detection procedure. The Oasis^® HLB cartridge outperformed other cleanup procedures, with analyte recoveries approaching 95%, while the Amberlite XAD‐7 procedure returned the lowest overall recoveries. The matrix rejection ability of each method was then determined using a simulated highly contaminated matrix, with the adsorbent resins showing a higher degree of matrix rejection, which is seen as a reduction in background noise in the UV chromatogram using 210 nm detection.     

Standardization of Histological Procedures for the Detection of Toxic Substances by Immunohistochemistry in Dipteran Larvae of Forensic Importance

Immunohistochemistry (IHC) technique is an alternative toxicological analysis to detect drugs in insects of forensic importance, but it requires thorough histological procedures. In this study, we tested different fixatives—phosphate‐buffered paraformaldehyde 4% (PP), Carnoy's fluid (CF), Kahle's solution (KS), ethanol in different concentrations, and ethanol associated to PP and CF, time of fixation and histological processes for dipteran larvae's tissue, aiming to develop a sample preparation protocol for IHC application. A suitable fixation was achieved using PP for 12 and 24 h, CF for 3 h, 70% ethanol for 19 days, and 70% ethanol/CF for 2 h/3 h. Postfixation using negative pressure, two immersions in xylene for 30 min each, and one in xylene plus paraffin for 45 min increased tissue preservation. An immunohistochemical test for cocaine detection was performed using monoclonal benzoylecgonine antibody from mouse, peroxidase‐conjugated anti‐mouse IgG and visualized by 3,3′‐diaminobenzidine method showed these histological procedures didn't compromise antigenicity.     

The Successful Recovery of Low Copy Number and Degraded DNA from Bones Exposed to Seawater Suitable for Generating a DNA STR Profile

A universal method allowing for DNA profiling from bones exposed to seawater has not been reported yet. This study refers on the identification of a body immersed in seawater for 8 months. The biological material for identification was the mandibular body, usually characterized by low success rates of DNA analysis. Initially, two extraction protocols were performed with negative results: one used for bones immersed in fresh water and a silica‐column procedure. A third protocol was performed, which combined the extraction of a higher amount of bone powder, the use of multi‐silica‐based extraction columns followed by a concentration step. This protocol allowed to obtain low copy number DNA and to generate a 12‐loci STR profile by combining conventional STR typing and mini‐STR technologies. This protocol could be suitable when human bones have been exposed to severe environmental conditions, and the available nuclear DNA is highly degraded and in low copy number.     

Development and Validation of a Method Using Dried Oral Fluid Spot to Determine Drugs of Abuse

A liquid chromatography–mass spectrometry method using dried oral fluid spots was developed and validated for the simultaneous quantification of cocaine, benzoylecgonine, cocaethylene, amphetamine, and 3,4‐methylenedioxymethamphetamine. The oral fluid was applied to a Whatman 903 grade paper and submitted to a drying time of 2.5 h. The extraction procedure was optimized by chemometric approach using simplex centroid design. Spots were extracted with a mixture of acetonitrile, buffer, and methanol. Calibration curves covered a linear concentration range of 40–500 ng/mL. Validation parameters of linearity, precision, accuracy, selectivity, carryover, matrix effects, and stability were evaluated and showed satisfactory results. Spot homogeneity was also satisfactory, with less than 15% of deviation from nominal concentration. Spot volume did not influence accuracy when less than 100 μL of the sample was applied to the spot. The validation of the proposed method suggests a potential application in different scenarios in toxicology.     

The Reliability of the Greulich and Pyle Atlas When Applied to a Modern Scottish Population

This study examines the reliability of age estimation utilizing the Greulich and Pyle atlas in relation to a modern Scottish population. A total of 406 left‐hand/wrist radiographs (157 females and 249 males) were age‐assessed using the Greulich and Pyle atlas. Analysis showed that there was a strong correlation between chronological age and estimated age (females R² = 0.939, males R² = 0.940). When age groups were broken down into year cohorts, the atlas over‐aged females from birth until 13 years of age. The pattern for males showed that the atlas under‐estimated age until 13 years of age after which point it consistently over‐aged boys between 13 and 17 years of age. This study showed that the Greulich and Pyle atlas can be applied to a modern population but would recommend that any analysis takes into account the potential for over‐ and under‐aging shown in this study.     

DART‐MS as a Preliminary Screening Method for “Herbal Incense”: Chemical Analysis of Synthetic Cannabinoids

Direct analysis in real time mass spectrometry (DART‐MS) served as a method for rapid high‐throughput screening of six commercially available “Spice” products, detecting various combinations of five synthetic cannabinoids. Direct analysis in real time is an ambient ionization process that, along with high mass accuracy time‐of‐flight (TOF)‐MS to 0.0001 Da, was employed to establish the presence of cannabinoids. Mass spectra were acquired by simply suspending a small portion of sample between the ion source and the mass spectrometer inlet. The ability to test minute amounts of sample is a major advantage when very limited amounts of evidentiary material are available. In addition, reports are widespread regarding the testing backlogs that now exist because of the large influx of designer drugs. This method circumvents time‐consuming sample extraction, derivatization, chromatographic, and other sample preparative steps required for analysis by more conventional mass spectrometric methods. Accordingly, the synthetic cannabinoids AM‐2201, JWH‐122, JWH‐203, JWH‐210, and RCS‐4 were identified in commercially available herbal Spice products, singly and in tandem, at concentrations within the range of 4–141 mg/g of material. Direct analysis in real time mass spectrometry decreases the time necessary to triage analytical evidence, and therefore, it has the potential to contribute to backlog reduction and more timely criminal prosecution.     

Internal Validation of RapidHIT®ID ACE Sample Cartridge and Assessment of the EXT Sample Cartridge*†

A new rapid DNA solution, the RapidHIT^®ID, can accommodate two different sample cartridges, ACE, for the analysis of a single swab and EXT, for the analysis of DNA extracts. An efficient internal validation designed for low‐throughput rapid DNA is described. An evaluation of the EXT sample cartridge is also described. Each cartridge generated profiles with sufficient data quality to meet CODIS eligibility in fewer than 120 min. The results exhibited 100% correlation when compared to conventional DNA typing methods. Precision, reproducibility, stochastic, mixture, and contamination experiments produced expected results. Sensitivity of the ACE sample cartridge was acceptable for buccal swab analysis. The sensitivity of the EXT sample cartridge is discussed. The ACE validation and the EXT evaluation utilized a minimalist, cost‐saving, efficient design to generate a validated RapidHIT^®ID instrument capable of producing genetic profiles from both extracted forensic DNA samples and buccal swab samples within 120 min.     

Temperature‐Dependent Postmortem Changes in Human Cardiac Troponin‐T (cTnT): An Approach in Estimation of Time Since Death

Estimation of time of death is an indispensible requirement of every medico‐legal autopsy, but unfortunately, there is not a single method by which it could be determined accurately. This study focused on the temperature‐dependent postmortem degradation of cardiac troponin‐T and its association with postmortem interval (PMI) in human. The analysis involved extraction of the protein, separation by denaturing gel electrophoresis (SDS‐PAGE), and visualization by Western blot using cTnT‐specific monoclonal antibodies. The area of the bands within a lane was quantified by scanning and digitizing the image using Gel Doc (Universal Hood). The results indicate a characteristic banding pattern among human cadavers (n = 6) and a pseudo‐linear relationship between percentage of cTnT degradation and the log of the time since death (r > 0.95), which can be used to estimate the postmortem interval. The data presented demonstrate that this technique can provide an extended time range during which PMI can be more accurately estimated.     

Comparative Analysis of Insect Succession Data from Victoria (Australia) Using Summary Statistics versus Preceding Mean Ambient Temperature Models

Minimum postmortem interval (mPMI) can be estimated with preceding mean ambient temperature models that predict carrion taxon pre‐appearance interval. But accuracy has not been compared with using summary statistics (mean ± SD of taxon arrival/departure day, range, 95% CI). This study collected succession data from ten experimental and five control (infrequently sampled) pig carcasses over two summers (n = 2 experimental, n = 1 control per placement date). Linear and exponential preceding mean ambient temperature models for appearance and departure times were constructed for 17 taxa/developmental stages. There was minimal difference in linear or exponential model success, although arrival models were more often significant: 65% of linear arrival (r² = 0.09–0.79) and exponential arrival models (r² = 0.05–81.0) were significant, and 35% of linear departure (r² = 0.0–0.71) and exponential departure models (r² = 0.0–0.72) were significant. Performance of models and summary statistics for estimating mPMI was compared in two forensic cases. Only summary statistics produced accurate mPMI estimates.     

Accuracy and Reliability of Total Body Mass Estimation Techniques from Stature and Bi‐iliac Breadth in Non‐Hispanic U.S. Whites from the Bass Donated Skeletal Collection

This paper tests the fidelity of a recent method that used the NHANES III dataset as a proxy to estimate total body mass from stature and bi‐iliac breadth in U.S. White males and females. The bi‐iliac breadths of 230 males and 152 females identified as non‐Hispanic U.S. White from the Bass Donated Skeletal Collection were measured, and along with stature from predonor paperwork, total body mass estimates were calculated and then compared to body masses recorded on predonor paperwork. Male and female samples were subdivided by body mass index (BMI [kg/m²]) categories established by the World Health Organization. Our results suggest that total body mass estimates can be accurately assessed provided that the individual is within 18.50 ≤ BMI ≤ 29.99 for White males and 18.50 ≤ BMI ≤ 24.99 for White females. Recommendations on how to report total body mass estimates are also presented.     

Monitoring of Levamisole Concentration in Serum of Traffic Participants after Cocaine Consumption

This study highlights the problem of levamisole‐adulterated cocaine in context of active traffic participation. For the purposes of levamisole concentration monitoring in human serum, an analytical method based on LC‐MS/MS and solid‐phase extraction was applied. A Luna 5 μm C18 (2) 100 A, 150 mm × 2 mm column and a mobile phase consisting of A (H₂O/methanol = 95/5, v/v) and B (H₂O/methanol = 3/97, v/v), both with 10 mM ammonium acetate and with 0.1% acetic acid (pH = 3.2), were used. The validation experiments demonstrated that the method applied was appropriate for levamisole quantification in human serum. For 23% of levamisole‐positive samples, the concentrations exceeded 20 ng/mL. Therefore, the interaction of this drug with cocaine has to be considered as important for active traffic participation. As a consequence, monitoring of levamisole concentration in human serum is recommended, as long as it is used as cocaine adulterant.     

Effectiveness of Single‐Nucleotide Polymorphisms to Investigate Cattle Rustling

Short tandem repeats (STR)s have been the eligible markers for forensic animal genetics, despite single‐nucleotide polymorphisms (SNP)s became acceptable. The technology, the type, and amount of markers could limit the investigation in degraded forensic samples. The performance of a 32‐SNP panel genotyped through OpenArrays^TM (real‐time PCR based) was evaluated to resolve cattle‐specific forensic cases. DNA from different biological sources was used, including samples from an alleged instance of cattle rustling. SNPs and STRs performance and repeatability were compared. SNP call rate was variable among sample type (average = 80.18%), while forensic samples showed the lowest value (70.94%). The repeatability obtained (98.7%) supports the used technology. SNPs had better call rates than STRs in 12 of 20 casework samples, while forensic index values were similar for both panels. In conclusion, the 32‐SNPs used are as informative as the standard bovine STR battery and hence are suitable to resolve cattle rustling investigations.     

Determining the Method Threshold of Identification via Gas Chromatography–Mass Spectrometry of Weathered Gasoline Extracted from Burnt Nylon Carpet,

The Organization of Scientific Area Committees defines threshold of identification as the minimum concentration of ignitable liquid identifiable from gas chromatographic‐mass spectrometry data using accepted pattern identification criteria. We propose a method for determining this threshold for gasoline based on base peak to qualifier ratios of six compounds. The ion ratios were established for each compound in the neat gasoline. These ratios were then compared to those obtained for gasoline and 98% weathered gasoline both spiked onto burnt nylon carpet at 20 ppt down 0.50 ppt, and recovered from the carpet using headspace extraction (ASTM 1412). Identification was confirmed if the compounds’ ion ratios fell within ±25% of that in the neat sample. We found that ion ratios for all samples were acceptable for six compounds at 1.60 and 0.80 ppt for extracted neat and extracted 98% weathered gasoline, respectively, illustrating potential for incorporating into Quality Assurance Programs.