Beyond the ridge pattern: multi-informative analysis of latent fingermarks by MALDI mass spectrometry

Abstract

After over a century, fingerprints are still one of the most powerful means of biometric identification. The conventional forensic workflow for suspect identification consists of (i) recovering latent marks from crime scenes using the appropriate enhancement technique and (ii) obtaining an image of the mark to compare either against known suspect prints and/or to search in a Fingerprint Database. The suspect is identified through matching the ridge pattern and local characteristics of the ridge pattern (minutiae). However successful, there are a number of scenarios in which this process may fail; they include the recovery of partial, distorted or smudged marks, poor quality of the image resulting from inadequacy of the enhancement technique applied, extensive scarring/abrasion of the fingertips or absence of suspect's fingerprint records in the database. In all of these instances it would be very desirable to have a technology able to provide additional information from a fingermark exploiting its endogenous and exogenous chemical content. This opportunity could potentially provide new investigative leads, especially when the fingermark comparison and match process fails. We have demonstrated that Matrix Assisted Laser Desorption Ionisation Mass Spectrometry and Mass Spectrometry Imaging (MALDI MSI) can provide multiple images of the same fingermark in one analysis simultaneous with additional intelligence. Here, a review on the pioneering use and development of MALDI MSI for the analysis of latent fingermarks is presented along with the latest achievements on the forensic intelligence retrievable.

Fatty Acid Structure and Degradation Analysis in Fingerprint Residues

“…GC-MS was used in 1999 to identify components of fingerprint residues, including free fatty acids, triglycerides, wax ester, amino acids, glycerol, cholesterol, and squalene [17], followed by several studies combining chromatography, mass spectrometry, and spectroscopic techniques [18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35]. Gender determination [21], donor classification [21][22][23][24][25], and aging studies [26][27][28][29][30][31][32] were among the major targets of fingerprint research recently.…”

“…Gender determination [21], donor classification [21][22][23][24][25], and aging studies [26][27][28][29][30][31][32] were among the major targets of fingerprint research recently. Francese et al show in their review article the power of MALDI mass spectrometry for the manifold analyses of fingerprints, even after aging [33].…”

Development of Laser Desorption Imaging Mass Spectrometry Methods to Investigate the Molecular Composition of Latent Fingermarks

“…Surface assistedlaser desorption/ionization-time-of-flight (SALDI-TOF) MS has been carried out for the detection of some fatty acids, dehydrated cholesterol, squalene, as well as the identification of explosives, drugs, and nicotine residues [8,18,19]. More recently, matrix-assisted-laser desorption/ionization (MALDI) TOF MS has been reported for the detection of endogenous substances, such as amino acids, fatty acids, peptides, dehydrated cholesterol, squalene, DAGs, and TAGs, as well as surfactants, polymers, drugs, pharmaceuticals, and explosives [20][21][22].…”

Lifestyle chemistries from phones for individual profiling

“…Due to its superb sensitivity (14), mass spectrometry (MS) is a powerful tool widely used for forensic applications (15) by providing either molecular (16)(17)(18)(19) or elemental analysis (20)(21)(22). Specific sets of known molecules are usually targeted in forensics applications, for example, to identify traces of illicit drugs or explosives (23)(24)(25)(26). However, individually targeting molecules for detection is not sufficient to describe the lifestyle of a given person, whereas a complete chemical signature obtained through the chemical analysis of a swab of the personal Significance This paper introduces the concept of skin-associated lifestyle chemistries found on personal belongings as a form of trace evidence.…”