Estimation of post-mortem interval using biochemical markers

Determining the post-mortem interval (PMI) or time of death is a critical step in most homicide or un-witnessed death investigations. However, the various methods currently used in estimating PMI yield large post-mortem windows and sometimes contradict one another. Traditional biochemical methods have identified a number of metabolites that change post mortem, but these have not been widely adapted for determining PMI because they failed to produce precise, reliable, and rapid results required by the forensic community. Recent developments in biochemical technologies are starting to identify biomarkers that may provide a much more accurate PMI estimation. These techniques are more sensitive and specific than traditional methods and can be standardised and statistically assessed, making them appealing methodologies. In this review, we discuss the use of biochemical methods for PMI determination in the early post-mortem period, with a particular focus on biochemical and cellular changes occurring in the blood. We also provide an overview of current biochemical methods and technologies that can be used to discover novel biomarkers that may help to determine PMI.