Identification of urine samples obtained in forensic cases by fourier transform infrared spectroscopy

Abstract

Forensic sciences are a multidisciplinary science that covers all branches of science for justice. Forensic genetics is one of the sub-branches of forensic sciences. It is a branch of science that contributes to establishing a connection between crime and criminal by using all kinds of biological evidence (blood, semen, saliva, urine, vaginal fluid, hair, hair, sweat, saliva, etc.) and reaching the perpetrator with the genetic information obtained. Serological and immunological tests are used in the identification of body fluids found as evidence at the crime scene. The number of serological tests used in the past and today is limited; not all body fluids can be analyzed routinely. Many of the existing tests are not directly specific to the body fluid but are intended to identify intermediate metabolites. One such example is the urine sample. In the identification of urine, the presence of creatinine and amines in the urine is often used. In addition, these tests require the expenditure of separate consumables to identify each body fluid. For this reason, with the development of technology, in recent years, the use of spectroscopic methods that provide cost-free and easy analysis in the identification of body fluids has increased. Fourier Transform Infrared (FTIR) spectroscopy is one of the spectroscopic methods used to identify body fluids from biological samples found at the crime scene without loss of quantity and without damaging the sample, quickly and without loss of consumables. This study investigated the identification of urine stains obtained from the crime scene with FTIR spectroscopy without using serological materials. Functional groups, which we can express as identification regions, were determined as 13 different distinguishing points in the relevant molecules and their usability in forensic serological analyses was determined.