Analysis of Polymers and Organic GSR from 3D Printed Firearm using Direct Analysis in Real-time Mass Spectrometry (DART-MS)
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Abstract
Several methods were developed in lab work, including forensic analysis of polymers & organic GSR from 3D printed firearms using Direct Analysis in Real Time Mass Spectrometry (DART-MS) for a wide variety of applications. Since its introduction, DART-MS has been studied for forensic use in areas including drug detection, gunshot residue, printer inks, and even insect identification. We used DART-MS to characterize the polymer evidence left behind by a 3D-printed firearm on cartridge cases, bullets, and the receiving surface. According to James Cizdziel, “There is concern with these 3D printed guns because they have no serial numbers. The fire gun barrels made with Acrylonitrile Butadiene Styrene (ABS), Polylactic Acid, PETG, Chlorinated Polyethylene (CPE) & Nylon were examined by DART-MS. The resulting cartridge cases, bullets & GSR are examined by Direct Analysis of Real Time-Mass Spectrometry”. It successfully detects and identifies the traces of polymer and organic GSR compounds on the bullets, cartridge cases, and in GSR collected from clothing. While detecting polymer in the trace evidence was challenging, DART-MS obtained clear spectra that matched the plastic from the gun from clothing used as a backdrop for test fire. According to the study, DART-MS readily detected three chemicals commonly found in firearm propellants (ethyl centralite, methyl centralite, and diphenylamine) on the bullet and cartridge case, as well as in the solvent wash of the GSR stub. The resulting cartridge cases, bullets, and gunshot residue (GSR) were examined by direct analysis in real time – mass spectrometry (DART-MS). High-resolution mass spectra detected polymer from the gun barrel on bullets and cartridge casings for a 0.38 special Caliber gun and, to a lesser extent, for a 0.22 Caliber 3D-printed gun. This study states that analysis of firearm trace evidence using DART-MS needs more attention & that the technique may be particularly useful for investigating crimes involving 3D-printed guns. I'm writing my review paper on this topic because it's important for addressing challenges related to 3D-printed firearms. These weapons often don't have traditional serial numbers, making them difficult to trace. However, by analyzing polymer residues left on bullets, cartridge cases, or nearby surfaces, investigators can potentially identify the firearm used. The unique chemical makeup of polymers used in 3D printing can help ink the residue back to a specific gun or even a particular 3D printer model. This study states that analysis of firearm trace evidence using DART-MS needs more attention & that the technique may be particularly useful for investigating crimes involving 3D-printed guns.
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Falardeau MS, Mireault C, Daoust B, Muehlethaler C. Chemical analysis of polymers used for 3D printing of firearms. Forensic Sci Int. 2024;357:111999. Available from: https://doi.org/10.1016/j.forsciint.2024.111999
Khandasammy SR. Organic Gunshot Residue: Detection, Identification, and Characterization for Forensic Purposes [dissertation]. Albany (NY): State University of New York at Albany; 2022. Available from: https://scholarsarchive.library.albany.edu/legacy-etd/2938/
Gandy L, Najjar K, Terry M, Bridge C. A novel protocol for the combined detection of organic, inorganic gunshot residue. Forensic Chem. 2018;8:1–10. Available from: https://doi.org/10.1016/j.forc.2017.12.009
Krishna S, Ahuja P. A chronological study of gunshot residue (GSR) detection techniques: a narrative review. Egypt J Forensic Sci. 2023;13(1):51. Available from: https://ejfs.springeropen.com/articles/10.1186/s41935-023-00369-8
Goudsmits E, Sharples GP, Birkett JW. Recent trends in organic gunshot residue analysis. TrAC Trends Anal Chem. 2015;74:46–57. Available from: https://doi.org/10.1016/j.trac.2015.05.010
Ledergerber TD, Feeney W, Arroyo L, Trejos T. A feasibility study of direct analysis in real time-mass spectrometry for screening organic gunshot residues from various substrates. Anal Methods. 2023;15(36):4744–57. Available from: https://pubs.rsc.org/en/content/articlelanding/2023/ay/d3ay01258a
Serol M, Ahmad SM, Quintas A, Família C. Chemical analysis of gunpowder and gunshot residues. Molecules. 2023;28(14):5550. Available from: https://doi.org/10.3390/molecules28145550
Black O, Cody R, Edwards D, Cizdziel JV. Identification of polymers and organic gunshot residue in evidence from 3D-printed firearms using DART-mass spectrometry: A feasibility study. Forensic Chem. 2017;5:26–32. Available from: https://doi.org/10.1016/j.forc.2017.05.003
Ball P. Development of a DART-Mass Spectral Database for 3D-Printed Firearm Polymers, and Airborne Mercury at Three Lakes in North Mississippi [honors thesis]. University, MS: University of Mississippi; 2019. Available from: https://egrove.olemiss.edu/hon_thesis/1106/
Yue H, He F, Zhao Z, Duan Y. Plasma‐based ambient mass spectrometry: Recent progress and applications. Mass Spectrom Rev. 2023;42(1):95–130. Available from: https://doi.org/10.1002/mas.21712
Sen R. High-resolution mass spectrometry for the analysis of interfacial kinetics of organic surface reactions [doctoral dissertation]. 2017. Available from: https://pubs.acs.org/doi/10.1021/acs.langmuir.6b00427
Zhu SZ, Zhou BW, Zhang L, Zhang J, Guo YL. Rapid characterization of polymer materials using arc plasma-based dissociation-mass spectrometry. Anal Chem. 2021;93(36):12480–6. Available from: https://doi.org/10.1021/acs.analchem.1c02904
Gupta S, Samal N. Application of direct analysis in real-time mass spectrometry (DART-MS) in forensic science: a comprehensive review. Egypt J Forensic Sci. 2022;12(1):17. Available from: https://ejfs.springeropen.com/articles/10.1186/s41935-022-00276-4
Feider CL, Krieger A, DeHoog RJ, Eberlin LS. Ambient ionization mass spectrometry: recent developments and applications. Anal Chem. 2019;91(7):4266–90. Available from: https://doi.org/10.1021/acs.analchem.9b00807
Black O, Cody R, Edwards D, Cizdziel JV. Identification of polymers and organic gunshot residue in evidence from 3D-printed firearms using DART-mass spectrometry: A feasibility study. Forensic Chem. 2017;5:26–32. Available from: https://scholar.google.com/citations?view_op=view_citation&hl=en&user=brFmwCEAAAAJ&citation_for_view=brFmwCEAAAAJ:HDshCWvjkbEC
Serol MDLC. Chemometric profile of gunpowder [master's thesis]. Monte da Caparica (PT): Egas Moniz School of Health and Science; 2022. Available from: https://www.proquest.com/openview/9692607b12b662a736b2979dc7a95b62/1?pq-origsite=gscholar&cbl=2026366&diss=y
AlShamsi MA. Firearms evidence collection. In: Manual of Crime Scene Investigation. Boca Raton (FL): CRC Press; 2022. p.193–204. Available from: https://www.taylorfrancis.com/chapters/edit/10.4324/9781003129554-13/firearms-evidence-collection-mohammad-alshamsi
Bonnar C, Moule EC, Lucas N, Seyfang KE, Dunsmore RP, Popelka-Filcoff RS, et al. Tandem detection of organic and inorganic gunshot residues using LC–MS and SEM-EDS. Forensic Sci Int. 2020;314:110389. Available from: https://doi.org/10.1016/j.forsciint.2020.110389
Wenzinger ZE, Wetzel S, Bernarding B, Viator J, Kohlhepp B, Marshall P. The relevance of current forensic firearms examination techniques when applied to 3D printed firearms. J Forensic Sci. 2024;69(2):659–68. Available from: https://doi.org/10.1111/1556-4029.15467
Lennert E. Analysis and characterization of smokeless powders and smokeless powder residues [master's thesis]. Orlando (FL): University of Central Florida; 2022. Available from: https://stars.library.ucf.edu/etd2020/1476/
Harshey A, Srivastava A, Das T, Nigam K, Shrivastava R, Yadav VK. Trends in gunshot residue detection by electrochemical methods for forensic purpose. J Anal Test. 2021;5:258–69. Available from: http://dx.doi.org/10.1007/s41664-020-00152-x
Guo T, Yong W, Jin Y, Zhang L, Liu J, Wang S, et al. Applications of DART‐MS for food quality and safety assurance in food supply chain. Mass Spectrom Rev. 2017;36(2):161–87. Available from: https://doi.org/10.1002/mas.21466
Rehman HU. Recent trends in chemical profiling of GSR from trace evidence. 2023. Available from: https://www.researchgate.net/publication/377204808_RECENT_TRENDS_IN_CHEMICAL_PROFILING_OF_GSR_FROM_TRACE_EVIDENCE
Bonnar C. On the integrated analysis and forensic interpretation of gunshot residues [doctoral dissertation]. Adelaide (AU): Flinders University, College of Science and Engineering; 2023. Available from: https://theses.flinders.edu.au/view/da7e817c-186e-4eb4-a5ab-76afe30e5a0a/1
Black OB. Physical and chemical trace evidence from 3D-printed firearms, and use of a quadcopter for targeted sampling of gaseous mercury in the atmosphere [master's thesis]. University, MS: University of Mississippi; 2019. Available from: https://egrove.olemiss.edu/etd/1739/
Castañeda FN, Prince DL, Peirano SR, Giovannoni S, Echevarría RN, Keunchkarian S, et al. New sorbents for sample pretreatment: development and applications. TrAC Trends Anal Chem. 2024:117924. Available from: https://www.researchgate.net/publication/383324527_New_sorbents_for_sample_pretreatment_development_and_applications
Li SY, Turner J, Golightly S, Zelbst P, Yu J. Potential impacts of 3D modeling and 3D printing in firearm toolmark examinations. J Forensic Sci. 2021;66(6):2201–7. Available from: https://doi.org/10.1111/1556-4029.14790
Black O, Smith SC, Roper C. Advances and limitations in the determination and assessment of gunshot residue in the environment. Ecotoxicol Environ Saf. 2021;208:111689. Available from: https://doi.org/10.1016/j.ecoenv.2020.111689
Bain RM, Pinedo TJ, Klapec DJ, Mulligan CC, Fedick PW. Post-burn and post-blast rapid detection of trace and bulk energetics by 3D-printed cone spray ionization mass spectrometry. Talanta Open. 2024;10:100377. Available from: https://doi.org/10.1016/j.talo.2024.100377
Wesdemiotis C, Williams‐Pavlantos KN, Keating AR, McGee AS, Bochenek C. Mass spectrometry of polymers: a tutorial review. Mass Spectrom Rev. 2024;43(3):427–76. Available from: https://doi.org/10.1002/mas.21844
Chen M, Huang Q, Li Y, Li B, Zhang Z, Zhang L, et al. Ambient ionization mass spectrometry for rapid detection of biological warfare agents and their simulants. Microchem J. 2023;194:109275. Available from: https://doi.org/10.1016/j.microc.2023.109275
Prada-Tiedemann P, DeGreeff L, Schultz C. Forensic and security applications of substance detection canines. In: Olfactory Research in Dogs. Cham: Springer International Publishing; 2023. p.237–90. Available from: https://www.researchgate.net/publication/374892624_Forensic_and_Security_Applications_of_Substance_Detection_Canines
Carter S, Fisher A, Gibson B, Marshall J, Russell B, Whiteside I. Atomic spectrometry update: review of advances in the analysis of metals, chemicals and materials. J Anal At Spectrom. 2017;32(11):2068–117. Available from: https://pubs.rsc.org/en/content/articlelanding/2017/ja/c7ja90046e