Journal of Punjab Academy of Forensic Medicine & Toxicology
SCOPUS
  • Year: 2023
  • Volume: 23
  • Issue: 1

Application of ATR FT-IR spectroscopy and chemometrics for the differentiation of brown shoe polish stains as forensic evidence

  • Author:
  • Spriha Sharma1, Sweety Sharma2, Rajinder Singh3,*
  • Total Page Count: 9
  • Published Online: Dec 19, 2023
  • Page Number: 105 to 113

1Assistant Professor, Department of Forensic Science, Chandigarh University, Mohali, India

2Assistant Professor, National Forensic Science University, Delhi Campus, India

3Professor, Department of Forensic Science, Punjabi University, Patiala, Punjab–147002, India

*Corresponding Author: Dr. Rajinder Singh, Professor, Department of Forensic Science, Punjabi University, Patiala, Punjab-147002, India, E-mail: rajchandel7@gmail.com Contact : +91-8968741133

Online published on 19 December, 2023.

Abstract

Shoe polish stains can be encountered as trace evidence in criminal cases like physical/sexual assault, burglary, murder and theft. It can therefore, serve as crucial evidence to establish a link between the suspect, the victim, and the crime scene.

In the present study, total 17 brown shoe polish samples of different brands were collected and analysed using Attenuated Total Reflectance (ATR) Fourier Transform Infrared (FT-IR) spectroscopy in combination with chemometrics method that is PCA for the discrimination purpose. In addition, the effect of substrates is also studied to simulate the actual case conditions.

The current approach delivered discrimination power up to 100% for the differentiation of different brands of brown shoe polish samples. Further, blind test was performed to validate the results by analysing six unknown samples which were classified and linked accurately with their respective source samples.

The developed methodology demonstrates a great potential of ATR FT-IR to analyse evidence in a rapid, novel and non-destructive manner.

Keywords

ATR FT-IR, Spectroscopy, Chemometrics, Shoe Polish