Chemometrics applied to the comparison of synthetic fibers by MSP in Forensic Sciences

Ghedjati, Hamza; SebaÏ, Abdesselam

Algerian Journal of Forensic Sciences and Criminology
Volume 1, Numéro 1, Pages 14-18
2023-07-16

Chemometrics Applied To The Comparison Of Synthetic Fibers By Msp In Forensic Sciences

Authors : Ghedjati Hamza . Sebaï Abdesselam .

Abstract

In this article we discuss the advantages of utilizing chemometric approaches in the field of forensic science to resolve and compare synthetic textile fibers. It is well known that micro-spectro-photometry (MPS) is a rapid, accurate and reproducible method used in comparing colored fibers; however, these comparisons are often hampered by raw spectra showing little details or fewer points to allow more precise distinctions. The use of chemometric methods applied to spectroscopic data using multivariate statistics can provide valuable information especially when considering complex data sets. Such efforts could save time and resources in forensic examinations and help minimize variability between individual examiners. Differentiating a group of samples using chemometric analysis increases the probative value in comparing fibers by decreasing the probability of erroneous combinations. In this study, the visible spectra subtracted and normalized sixteen dyed synthetic samples with different dye compositions ranging from green, blue and red. Each of these samples was differentiated by three methods Hierarchical Ascending Classification (HAC), Principal Component Analysis (PCA) and Linear Discriminate Analysis (LDA). The results of the HAC and the PCA were consistent, showing similar spectra gathering near each other. Analysis of the LDA revealed a total classification accuracy of 100%, which corroborates the results of Hotelling test (T2).