Forensics: evidence examination via Raman spectroscopy

Abstract

<jats:title>Abstract</jats:title> <jats:p>Forensic science can be broadly defined as the application of any of the scientific method to solving a crime. Within forensic science there are many different disciplines, however, for the majority of them, five main concepts shape the nature of forensic examination: transfer, identification, classification/individualization, association, and reconstruction. The concepts of identification, classification/individualization, and association rely greatly on analytical chemistry techniques. It is, therefore, no stretch to see how one of the rising stars of analytical chemistry techniques, Raman spectroscopy, could be of use. Raman spectroscopy is known for needing a small amount of sample, being non-destructive, and very substance specific, all of which make it ideal for analyzing crime scene evidence. The purpose of this chapter is to show the state of new methods development for forensic applications based on Raman spectroscopy published between 2015 and 2017.</jats:p>

Detection of Toxic Chemicals on Ground by Stand‐off Raman Spectroscopy

“…These features allow the analysis of unknown contaminants on the ground surface by a stand‐off method at a distance near 1 m . Many of the recent studies on Raman spectroscopy for toxic chemical analysis focused on surface‐enhanced Raman spectroscopy to maximize the intensity of the analytical signals, which have limitations for the rapid onsite detection of contaminants on the ground surface. Stand‐off Raman spectroscopy is emerging as a noble method that can rapidly detect contamination of the ground surface by toxic chemicals such as CWAs.…”

Photoluminescent carbon nanomaterials for sensing of illicit drugs: focus

“…Many microscale devices, including UV-vis spectrometer, infrared spectrometer, electrochemical apparatus, gaschromatography-mass spectrometry, ion mobility mass spectrometry, Raman scattering spectrometer, have been used for field testing of illicit drugs. [38][39][40][41][42] Although they offer advantages of sensitivity and specificity/selectivity, the requirement of experienced technicians to operate the system and to analyze the data is a concern for field testing. High cost, especially mass spectrometry, is a general concern.…”

Portable Raman spectroscopy applied to the study of drugs of abuse

“…According to the scientific working group for the analysis of seized drugs (SWGDRUG), Raman spectroscopy is considered a selective technique, Category A, because it provides chemical information at the structural level, similar to infrared spectroscopy, mass spectrometry, nuclear magnetic resonance spectroscopy, and X‐ray diffraction [21]. Furthermore, Raman spectroscopy has important advantages: It can be applied to any physical state of matter, it does not suffer from water interference, it does not require sample preparation or large sample volumes, it is non‐invasive and non‐destructive, and it is available in a portable form [17,20,22,23]. This portability allows analysis in the field and even by remote operation [24,25].…”

“…In this context, Raman spectroscopy is an analytical technique with great potential to complement current screening and confirmatory tests [16][17][18][19][20]. According to the scientific working group for the analysis of seized drugs (SWGDRUG), Raman spectroscopy is considered a selective technique, Category A, because it provides chemical information at the structural level, similar to infrared spectroscopy, mass spectrometry, nuclear magnetic resonance spectroscopy, and X-ray diffraction [21].…”