Lim Ka Khei , Rajesh Verma , Eva Lee Yin Tan , Dzulkiflee Ismail , Muhammad Naeim Mohamad Asri
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引用次数: 1
Abstract
Nail polish can be important evidence in crimes like murder, rape, and suicides. Due to its prevalence, it can be important corroborative evidence in crime reconstruction. This paper reports the use of non-destructive ATR-FTIR spectroscopy combined with chemometrics for the discrimination of 79 nail polish samples of 8 brands. Differences in peak patterns, their absorbance, and the presence or absence of specific components in the chemical composition were examined in the ATR-FTIR technique prior to the discrimination with the statistical PLS-DA model. An excellent classification of samples was obtained according to the brands. The performance of PLS-DA through receiver operating characteristic (ROC) curves shows near-perfect results for the classification of the nail polish brands. Because nail polish can be found on many types of substrates such as paper, jeans, plastic, cloth, etc at the crime scene, we have tested all the unknown traces on such substrates and again, all the unknown samples (100%) in six substrates viz. cotton, jeans, white paper, polyester, tissue and nylon were correctly attributed to their source brand using the already trained PLS-DA model. The proof of concept demonstrated has potential applications in forensic casework.
期刊介绍:
Forensic Chemistry publishes high quality manuscripts focusing on the theory, research and application of any chemical science to forensic analysis. The scope of the journal includes fundamental advancements that result in a better understanding of the evidentiary significance derived from the physical and chemical analysis of materials. The scope of Forensic Chemistry will also include the application and or development of any molecular and atomic spectrochemical technique, electrochemical techniques, sensors, surface characterization techniques, mass spectrometry, nuclear magnetic resonance, chemometrics and statistics, and separation sciences (e.g. chromatography) that provide insight into the forensic analysis of materials. Evidential topics of interest to the journal include, but are not limited to, fingerprint analysis, drug analysis, ignitable liquid residue analysis, explosives detection and analysis, the characterization and comparison of trace evidence (glass, fibers, paints and polymers, tapes, soils and other materials), ink and paper analysis, gunshot residue analysis, synthetic pathways for drugs, toxicology and the analysis and chemistry associated with the components of fingermarks. The journal is particularly interested in receiving manuscripts that report advances in the forensic interpretation of chemical evidence. Technology Readiness Level: When submitting an article to Forensic Chemistry, all authors will be asked to self-assign a Technology Readiness Level (TRL) to their article. The purpose of the TRL system is to help readers understand the level of maturity of an idea or method, to help track the evolution of readiness of a given technique or method, and to help filter published articles by the expected ease of implementation in an operation setting within a crime lab.