Forensic Chemistry最新文献

Incorporating organic gunshot residue into the forensic workflow: A study of preservation and stability of the pGSR and OGSR

IF 2.6 3区医学

Forensic Chemistry Pub Date : 2025-03-22 DOI: 10.1016/j.forc.2025.100651

Kourtney A. Dalzell , Thomas Ledergerber , Tatiana Trejos , Luis E. Arroyo

{"title":"Incorporating organic gunshot residue into the forensic workflow: A study of preservation and stability of the pGSR and OGSR","authors":"Kourtney A. Dalzell , Thomas Ledergerber , Tatiana Trejos , Luis E. Arroyo","doi":"10.1016/j.forc.2025.100651","DOIUrl":"10.1016/j.forc.2025.100651","url":null,"abstract":"<div><div>In recent years, trace evidence examiners started to assess the value of incorporating two complementing analytical measurements: primer residue (pGSR) and organic gunshot residue (OGSR) data, aiming to strengthen firearms-related investigations. Still, there is a need to understand the cost-benefit of any method's modification for collecting, analyzing, and interpreting the combined information. This study aims to answer practical questions concerning optimal storage conditions for OGSR and pGSR, the feasibility of sequential analysis on the same sample, and whether pGSR or OGSR should be analyzed first. Samples were collected from shooters (<em>n</em> = 128) using a standard carbon adhesive stub. The stability of OGSR and pGSR was evaluated at the time elapsed from collection at the scene until analysis at the laboratory (1, 2 days, 1, 2 weeks, and 1, 2, 6 months) and storage conditions (room temperature or freezer). The experimental design includes the effect of the analysis sequence by either liquid chromatography-mass spectrometry (LC-MS/MS) and scanning electron microscopy energy dispersive X-ray spectrometry (SEM-EDS) on the detection rates. The results indicate a multi-testing approach does not compromise the integrity of pGSR or OGSR evidence when following appropriate protocols. The detection of OGSR and pGSR is not significantly different at the studied storage conditions or times when samples are preserved in sealed SEM stubs. These findings may alleviate some concerns regarding the feasibility of conducting an OGSR examination on samples that cannot be submitted to the laboratory immediately after collection and assist agencies in establishing preservation, storage, and acceptance criteria for future adoption.</div></div>","PeriodicalId":324,"journal":{"name":"Forensic Chemistry","volume":"44 ","pages":"Article 100651"},"PeriodicalIF":2.6,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143706322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Extraction approaches for A-230, A-234, VX, and sarin nerve agents from surface coatings

IF 2.6 3区医学

Forensic Chemistry Pub Date : 2025-03-22 DOI: 10.1016/j.forc.2025.100658

Tomáš Rozsypal

{"title":"Extraction approaches for A-230, A-234, VX, and sarin nerve agents from surface coatings","authors":"Tomáš Rozsypal","doi":"10.1016/j.forc.2025.100658","DOIUrl":"10.1016/j.forc.2025.100658","url":null,"abstract":"<div><div>Nerve agents are among the most hazardous chemical warfare agents (CWAs) due to their extreme toxicity. This study optimized methods for extracting CWAs (A-230, A-234, VX, and sarin) from surface coatings, a common but chemically complex matrix in urban environments. Four types of coatings (nitrocellulose, polyurethane, acrylic, and alkyd) were tested using bulk, wipe, and scrape extraction approaches with various solvents. Versatile methods were successfully developed for all four analytes across all four matrices, and recoveries were also determined for additional CWAs (soman, cyclosarin, and sulfur mustard). Bulk extraction consistently achieved the highest recoveries, while wipe extraction offered a practical alternative with slightly reduced efficiency. Scrape extraction exhibited high variability and was unsuitable for volatile compounds like sarin. The methods were evaluated using gas chromatography with flame ionization detection, demonstrating robust analytical performance, including high sensitivity, precision, minimized matrix effects, and validated accuracy through spiking recoveries. Persistence studies revealed slow dissipation rates in surface coatings, underscoring their forensic potential when other matrices yield only degradation products. A-230 and A-234 were detectable in all coatings for up to 56 days, whereas sarin dissipated rapidly, especially in acrylic paint. VX remained primarily in surface layers due to its high viscosity and limited diffusion. These findings highlight the importance of tailoring extraction methods to specific matrices and agents. Coatings, with their prolonged retention of CWAs, not only provide significant forensic value but also emphasize the need for targeted decontamination strategies to mitigate environmental and human health risks.</div></div>","PeriodicalId":324,"journal":{"name":"Forensic Chemistry","volume":"44 ","pages":"Article 100658"},"PeriodicalIF":2.6,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143706321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Analysis of substituted Cathinones and fentanyl analogs by gas chromatography-infrared spectroscopy (GC-IRD) using nitrogen carrier gas

IF 2.6 3区医学

Forensic Chemistry Pub Date : 2025-03-18 DOI: 10.1016/j.forc.2025.100654

Marcus L. Warner

{"title":"Analysis of substituted Cathinones and fentanyl analogs by gas chromatography-infrared spectroscopy (GC-IRD) using nitrogen carrier gas","authors":"Marcus L. Warner","doi":"10.1016/j.forc.2025.100654","DOIUrl":"10.1016/j.forc.2025.100654","url":null,"abstract":"<div><div>Substituted cathinones and fentanyl analogs that are positional isomers can produce similar mass spectra and retention times, which poses challenges for their identification. A gas chromatography-infrared spectroscopy (GC-IRD) method, developed using nitrogen as the carrier gas, was employed as a complimentary technique to gas chromatography-mass spectroscopy (GC–MS) for the accurate identification of positional isomers. Due to the global helium shortage and since Agilent helium (nitrogen switch) conservation modules were currently in use, nitrogen was selected and a novel method was developed for the analysis of controlled substances. A total method run time of 26 min for the analysis of 29 certified reference materials comprised of substituted cathinones and fentanyl analogs was achieved. A drug mixture was also analyzed to evaluate the resolution and retention time. Standards were prepared at concentrations of 100 μg/mL, 1 mg/mL and 2 mg/mL and analyzed over a 3-day period, where the 2 mg/mL concentrations of the standards were run in triplicate on day 1 and once on days 2 and 3. Twenty-seven of the standards were identified with a library match of 0.98 or higher for the 1 mg/mL concentration. Each standard experienced a retention time (RT) coefficient of variation (%CV) less than 3 %. For the drug mixture peak resolution exceeded 1.5 for each component. The GC-IRD validated method was found to be a suitable complementary analysis technique to GC–MS for analyzing substituted cathinones and fentanyl analogs, as demonstrated by the repeatable and reproducible RTs and library matches obtained during method validation.</div></div>","PeriodicalId":324,"journal":{"name":"Forensic Chemistry","volume":"44 ","pages":"Article 100654"},"PeriodicalIF":2.6,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143682670","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Chemical attribution signatures of nordiazepam for the determination of synthetic routes

IF 2.6 3区医学

Forensic Chemistry Pub Date : 2025-03-13 DOI: 10.1016/j.forc.2025.100653

Meng Jin , Zixuan Zhang , Xiaogang Lu , Qian Wang , Runli Gao , Fengxia Sun , Hongmei Wang

引用次数: 0

Evaluating machine learning methods on a large-scale of in silico fire debris data

IF 2.6 3区医学

Forensic Chemistry Pub Date : 2025-03-12 DOI: 10.1016/j.forc.2025.100652

Larry Tang , Slun Booppasiri , Michael E. Sigman , Mary R. Williams

{"title":"Evaluating machine learning methods on a large-scale of in silico fire debris data","authors":"Larry Tang , Slun Booppasiri , Michael E. Sigman , Mary R. Williams","doi":"10.1016/j.forc.2025.100652","DOIUrl":"10.1016/j.forc.2025.100652","url":null,"abstract":"<div><div>A large dataset of 240,000 fire debris samples have been generated in-silico using a data augmentation method at National Center for Forensic Science. The IS samples contain balanced data with 50 % samples having ignitable liquid residue and 50 % only having substrate components. In the big data era, this large dataset is useful for researchers to develop and implement their new machine learning methods. In this paper, we split the data into a training dataset and a test dataset. We then trained seven machine learning methods including logistic regression, least discriminant analysis, quadratic discriminant analysis, support vector machine, random forest, XGBoost, and neural network on an in-silico training dataset. The predictive accuracy and area under the ROC (AUC) of the models was evaluated and compared on both an in-silico test dataset and on an experimental fire debris dataset. In addition, we analyzed both TIS and TIC datasets. For the TIS dataset, neural network provides the highest AUC in both in-silico test and experimental fire debris dataset. Random forest shows the highest performance for the TIC dataset when we binned the retention index.</div></div>","PeriodicalId":324,"journal":{"name":"Forensic Chemistry","volume":"44 ","pages":"Article 100652"},"PeriodicalIF":2.6,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143619350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Water we waiting for? Evaluating a greener, safer, more cost-effective strategy for applying 1,2-indanedione to fingermarks on paper

IF 2.6 3区医学

Forensic Chemistry Pub Date : 2025-02-28 DOI: 10.1016/j.forc.2025.100650

Kristen T. Clarke , Scarlet L. Hopkins , Matthew N. Krosch , Sarah L. Cresswell , William J. Gee

{"title":"Water we waiting for? Evaluating a greener, safer, more cost-effective strategy for applying 1,2-indanedione to fingermarks on paper","authors":"Kristen T. Clarke , Scarlet L. Hopkins , Matthew N. Krosch , Sarah L. Cresswell , William J. Gee","doi":"10.1016/j.forc.2025.100650","DOIUrl":"10.1016/j.forc.2025.100650","url":null,"abstract":"<div><div>Developing fingermarks on paper-based evidence with 1,2-indanedione and zinc chloride is a fundamental evidence gathering methodology; however, the most widely-used carrier solvents to effect it, HFE-7100, will be phased out after 2025, necessitating new 1,2-indanedione formulations. While flammable hydrocarbon solvents have been suggested as suitable replacements for HFE-7100, the compromise to safety makes them unappealing long-term alternatives. This work evaluates a fundamentally different approach; a water-based, non-flammable xanthan gum gel medium hosting 1,2-indanedione that allows for detection of natural fingermarks. The optimised xanthan gum hydrogel formulation preserved fingermark ridge detail whereas the equivalent free-flowing ethanol/water-based solution did not. A natural fingermark depletion study demonstrated that hydrogels could be effective on simulated casework evidence, particularly 24 h after gel application. A validation study (<em>n</em> = 1920) comparing the 1,2-indanedione hydrogel formulation against a petroleum ether formulation found that, while the latter retained significantly better performance at this early stage of development, from a holistic frugal forensics perspective, hydrogels offer major benefits to cost and safety. This work also identified that refining the gel application method will likely improve the gel's performance, which will guide further development to deliver a safer, longer-term alternative to HFE-7100.</div></div>","PeriodicalId":324,"journal":{"name":"Forensic Chemistry","volume":"43 ","pages":"Article 100650"},"PeriodicalIF":2.6,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143550583","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Application of element and isotopic fingerprint features in nuclear forensics: A review

IF 2.6 3区医学

Forensic Chemistry Pub Date : 2025-02-08 DOI: 10.1016/j.forc.2025.100646

Ziao Li , Yang Shao , Min Luo , Lingling Ma , Diandou Xu

{"title":"Application of element and isotopic fingerprint features in nuclear forensics: A review","authors":"Ziao Li , Yang Shao , Min Luo , Lingling Ma , Diandou Xu","doi":"10.1016/j.forc.2025.100646","DOIUrl":"10.1016/j.forc.2025.100646","url":null,"abstract":"<div><div>Nuclear forensics can provide historical evidence for nuclear materials. This can be used to verify nuclear activities or trace the origin and intended use of materials. As a comprehensive discipline, most sample analysis techniques in nuclear forensics are adaptations of existing methodologies. The elemental signatures contain fundamental information about nuclear materials, while isotope signatures also significantly impact nuclear forensic research. This paper aims to give an overview about the recent developments and the state-of-art analytical methods for elemental signatures and isotope signatures in nuclear forensics. Thorough discussions are given in this paper covering a wide range of aspects, including sample pre-treatment methods, chemical separation techniques, source preparation, mass spectrometry measurement techniques, and multidimensional statistical methods. The element and isotopic signatures discussed in this article include uranium, plutonium, rare earth elements, impurity elements, and radiochronometers. The focus is on mass spectrometry-based detection methods that have been developed to enhance the efficiency, sample throughput and high-precision measurements of nuclear forensic. A detailed discussion is provided on the performance of these techniques, particularly regarding uncertainty, relative deviation and detection limits.</div></div>","PeriodicalId":324,"journal":{"name":"Forensic Chemistry","volume":"43 ","pages":"Article 100646"},"PeriodicalIF":2.6,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143394402","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A new “tailor-made” protocol for operational latent fingermarks’ development on unfired ammunition

IF 2.6 3区医学

Forensic Chemistry Pub Date : 2025-01-29 DOI: 10.1016/j.forc.2025.100645

Ravell Bengiat , Adi Dahan , Michal Levin-Elad , Nurit Atar , Yakir Liptz , Daniel Mandler , Joseph Almog

{"title":"A new “tailor-made” protocol for operational latent fingermarks’ development on unfired ammunition","authors":"Ravell Bengiat , Adi Dahan , Michal Levin-Elad , Nurit Atar , Yakir Liptz , Daniel Mandler , Joseph Almog","doi":"10.1016/j.forc.2025.100645","DOIUrl":"10.1016/j.forc.2025.100645","url":null,"abstract":"<div><div>Fingermarks’ (FM) development on unfired ammunition, found at shooting crime-scenes, provide key evidence in connecting a suspect to the crime. However, the standard FM enhancement technique for metal surfaces, ethyl cyanoacrylate (ECA) fuming, is often ineffective for this type of evidence, due to its high sensitivity to presence of residual water and salts from soil, leading to a non-selective polymerization on the entire surface. In this work, we have developed a new protocol for unfired brass ammunition suitable for standard operational conditions, and based on the “reverse-development” principle, to achieve higher sensitivity by targeting the surface, rather than the FM residues. This involves a pre-treatment stage using octyl cyanoacrylate (OCA) fuming, which provides a superhydrophobic protective layer to the FM ridges, followed by an electroless deposition reaction between a palladium complex (Na<sub>2</sub>PdCl<sub>4</sub>) and the brass surface. This long-chain cyanoacrylate derivative demonstrated excellent selectivity towards sebaceous residues in fingerprints, as its less reactive nature results in a polymerization that is unaffected by water, even after long exposure to moist soil (6 days, 80 % RH) prior to development. Moreover, the proposed process allowed the use of a concentrated Na<sub>2</sub>PdCl<sub>4</sub> solution, without the fear of over-development when immersing large quantities of ammunition simultaneously, thus affording a successful development of 92 % of a total of 320 FMs from 20 donors. Due to its high sensitivity, robustness, and suitability for large quantities, this simple-to-use protocol has shown a high potential for the future implementation in operational use by latent fingermarks laboratories and CSI field units.</div></div>","PeriodicalId":324,"journal":{"name":"Forensic Chemistry","volume":"42 ","pages":"Article 100645"},"PeriodicalIF":2.6,"publicationDate":"2025-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143144620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Instrumental color determination of local soils and its variation with elemental profiles

IF 2.6 3区医学

Forensic Chemistry Pub Date : 2025-01-27 DOI: 10.1016/j.forc.2025.100644

Melissa Liau, Jolene Low, Kang Hua Lee, Thiam Bon Lim

{"title":"Instrumental color determination of local soils and its variation with elemental profiles","authors":"Melissa Liau, Jolene Low, Kang Hua Lee, Thiam Bon Lim","doi":"10.1016/j.forc.2025.100644","DOIUrl":"10.1016/j.forc.2025.100644","url":null,"abstract":"<div><div>Forensic soil comparison typically relies on qualitative color description through visual observation and side-by-side comparison with standard color chips from the Munsell Soil Color Charts to determine a color notation. Soil color distinctions are then made according to the US National Soil Survey color contrast classes. However, this approach is inherently subjective due to the variations in human examiner’s color perception, which is further influenced by factors such as light intensity, viewing angle, and background contrast. Conversely, color-measuring instruments like spectrophotometers can detect subtle color variations reliably and with greater precision, including colors falling between the chips in Munsell Soil Color Charts. Color differences between a soil pair can be expressed numerically as <span><math><mrow><mi>Δ</mi><msub><mi>E</mi><mn>00</mn></msub></mrow></math></span> and a threshold based on <span><math><mrow><mi>Δ</mi><msub><mi>E</mi><mn>00</mn></msub></mrow></math></span> to distinguish soil colors can be established for objective color comparison. In this study, the colors of soils collected from Singapore parks (soils sampled from areas within 1 m, within the same park, and across different parks) were measured quantitatively using a spectrophotometer. The occurrences of false positives and negatives were calculated and evaluated for the visual and instrumental color comparison methods. We further investigated correlations between the color discrimination threshold based on <span><math><mrow><mi>Δ</mi><msub><mi>E</mi><mn>00</mn></msub></mrow></math></span> and a previous survey conducted on local soil’s elemental variability. The outcome of this study will help streamline soil analysis workflows in laboratories and strengthen the interpretation of forensic comparison of local soils.</div></div>","PeriodicalId":324,"journal":{"name":"Forensic Chemistry","volume":"43 ","pages":"Article 100644"},"PeriodicalIF":2.6,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143139905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Two AIE-actives difluoroboron compounds containing 3,4,5-trifluorophenyl group for latent fingerprints detection

IF 2.6 3区医学

Forensic Chemistry Pub Date : 2025-01-27 DOI: 10.1016/j.forc.2025.100643

Jiazhuang Tian , Yusong Du , Chunlin Chen, Xiangguang Li, Shulin Gao, Yanhua Yang, Shu Jiang

{"title":"Two AIE-actives difluoroboron compounds containing 3,4,5-trifluorophenyl group for latent fingerprints detection","authors":"Jiazhuang Tian , Yusong Du , Chunlin Chen, Xiangguang Li, Shulin Gao, Yanhua Yang, Shu Jiang","doi":"10.1016/j.forc.2025.100643","DOIUrl":"10.1016/j.forc.2025.100643","url":null,"abstract":"<div><div>To meet the needs of forensic identification, two 3,4,5-trifluorophenyl-substitued difluoroboron compounds, <strong>3F-ts-BF<sub>2</sub></strong> with a BF<sub>2</sub>-core and <strong>3F-ts-2BF<sub>2</sub></strong> with two BF<sub>2</sub>-cores, were synthesized. It was found that two compounds exhibited solvent-dependent fluorescence shifts in eight organic solvents with different polarities and aggregation-induced emission effects in CH<sub>3</sub>CN/water mixtures, which could be explained through time-dependent density functional theory calculations. Considering their aggregation-induced emission performances, the developers were prepared, which could clearly and quickly distinguish latent fingerprints on the surface of the glasses. In the bargain, the LFPs on the surfaces of five different substrates were also detected, it was found that the result of the LFPs imaging based on compound <strong>3F-ts-BF<sub>2</sub></strong> was better than that of compound <strong>3F-ts-2BF<sub>2</sub></strong>, which was surmised that it was possibly related to the uncoordinated amide linkage moiety in compound <strong>3F-ts-BF<sub>2</sub></strong>. This work provided a reference for molecular design using for latent fingerprints detection.</div></div>","PeriodicalId":324,"journal":{"name":"Forensic Chemistry","volume":"42 ","pages":"Article 100643"},"PeriodicalIF":2.6,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143144619","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0