Chemical detectives: solving mysteries through chemistry

A tiny carpet fiber. The pattern of blood droplets on a wall. The chemicals in duct tape.

These can all help detectives decipher a crime scene. Forensic scientists analyze every detail collected at the scene, looking for clues that explain what happened and who was involved.

Chemistry is vital in forensic science. With chemistry, forensic scientists can paint a picture of what happened, sometimes on a molecular level. Chemical analysis can reveal how long ago a person died, which gunshot the fatal bullet, and where the tape that tied them up was manufactured.

For chemical analysis to be useful for solving mysteries, it needs to be based on solid research. To recognize the contribution research makes to this field, National Chemistry Week 2016opens in new tab/window focuses on the theme “solving mysteries through chemistry.”

To celebrate, we have curated a collection of articles published in Elsevier’s chemistry journals this year that highlight this contribution. From detecting and analyzing fingerprints to testing paper used in forgeries, these articles give a broad overview of the research that supports forensics. We hope you enjoy reading the collection, which is free to access until January 13, 2017.

Detecting forgeries and fingerprints

When fingerprints have been left for a long time, they can be difficult to detect and analyze. Nanotechnology has led to a wave of new materials that aim to visualize latent fingerprints, by sticking well to the ridges and being easy to detect. In a review in Synthetic Materialsopens in new tab/window, Dr. Adam Leśniewskiopens in new tab/window, a researcher at the Institute of Physical Chemistry, Polish Academy of Sciencesopens in new tab/window, looks at the use of silica-based materials that incorporate nanoparticles and quantum dots, among other substances, as more effective methods to identify latent fingerprints. At the other end of the spectrum, an ancient pigment could be just as helpful. In a paper in Dyes and Pigmentsopens in new tab/window, researchers from Curtin Universityopens in new tab/window in Australia propose an ancient dye that can has near-infrared (NIR) luminescence. They demonstrate that the pigment Egyptian blue – the world’s oldest synthetic pigment – enables forensic scientists to detect otherwise invisible latent fingerprints.

Chemical fingerprinting of fuels can reveal fraud that causes significant damage to engines and machinery. Lubricating oil reduces friction and keeps machines running smoothly, but because it is so valuable it is subject to fakery, with people deliberately adulterating it to make money. Using a fingerprinting analysis technique described in the journal Fuelopens in new tab/window, researchers at Environment Canadaopens in new tab/window characterized new and used lube oils, showing how the method could help identify fraudulent products.

In other cases of fraud, paper analysis can help forensic scientists understand where a forged document originated. In a new study in Journal of Organometallic Chemistryopens in new tab/window, researchers from Panjab Universityopens in new tab/window in India explore the use of a technique called chemometrics to characterize and discriminate paper samples. They characterized 24 paper brands by matching peaks with cellulose and fillers – constituents of paper – and found that the chemometrics could discriminate 99.64 percent of samples.

Special collection: Solving mysteries through chemistry

Read more about these studies and many others in our special collection to celebrate National Chemistry Week 2016opens in new tab/window. This collection of articles is free to access until January 13, 2017.

• Blood drop patterns: Formation and applicationsopens in new tab/window, Advances in Colloid and Interface Science (May 2016)

• Smart platform for the time since death determination from vitreous humor cysteineopens in new tab/window, Biosensors and Bioelectronics

  (December 2016)

• Kernel-based methods for source identification using very small particles from carpet fibersopens in new tab/window, Chemometrics and Intelligent Laboratory Systems (October 2016)

• Microwave-assisted on-spot derivatization for gas chromatography–mass spectrometry based determination of polar low molecular weight compounds in dried blood spotsopens in new tab/window, Journal of Chromatography A (September 2016)

• Application of infrared spectroscopy and pyrolysis gas chromatography for characterisation of adhesive tapesopens in new tab/window, Journal of Organometallic Chemistry (December 2016)

• A fast and reliable method for GHB quantitation in whole blood by GC–MS/MS (TQD) for forensic purposesopens in new tab/window, Journal of Pharmaceutical and Biomedical Analysis (February 2016)

• Gunshot residues (GSR) analysis of clean range ammunition using SEM/EDX, colorimetric test and ICP-MS: A comparative approach between the analytical techniquesopens in new tab/window, Microchemical Journal (November 2016)

• Fourier transform infrared spectroscopy and chemometrics for the characterization and discrimination of writing/photocopier paper types: Application in forensic document examinationsopens in new tab/window, Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy (January 2017)

• Lead isotope ratios for bullets, forensic evaluation in a Bayesian paradigmopens in new tab/window, Talanta (January 2016)

• Characterization and differentiation of chemical fingerprints of virgin and used lubricating oils for identification of contamination or adulteration sourcesopens in new tab/window,

  Fuel (January 2016)

• Micronised Egyptian blue pigment: A novel near-infrared luminescent fingerprint dusting powderopens in new tab/window, Dyes and Pigments (September 2016)

• Hybrid organic–inorganic silica based particles for latent fingermarks development: A reviewopens in new tab/window, Synthetic Metals (March 2016)