Species Determination and Discrimination of Animal Blood: A Multi-Analytical Spectroscopic-Chemometrics Approach in Forensic Science

ABSTRACT

@#Introduction: Non-destructive analysis of biological evidence has been paramount importance in the forensic investigation since it is an effective tool in establishing a standard that could be employed to differentiate ensuing destructive tests of bio-fluids upon sample division between the plaintiff and defendant. Species identification of bloodstain found at the crime scene is very crucial in routine forensic work as this can assist the initial investigation by incorporating or excluding stain that is not human and to identify its origin if animal blood is involved. Methods: In this research, identification and discrimination of various blood species collected from seven domestic animals namely chicken, cow, deer, duck, fish, goat, and pig were investigated using non-destructive analytical techniques; ATRFTIR and visible spectroscopy coupled with principal component analysis and linear discriminant analysis (PCALDA) for classification purposes. Results: ATR-FTIR FTIR spectroscopic study demonstrated a higher rate of successful classification (≥ 90%) as compared to visible spectroscopic technique. Conclusion: ATR-FTIR spectroscopy has been an ideal, robust, and suitable tool for determining the blood species of domestic animals. The predictive model from PCA-LDA analysis can be utilised to produce higher classification rate for species determination from blood traces.