Year: 2025 | Month: November | Volume: 15 | Issue: 11 | Pages: 60-71
DOI: https://doi.org/10.52403/ijhsr.20251109
Vitreous Humor Hypoxanthine and Potassium as Markers for Post-mortem Interval Estimation: A UPLC-Based Study
Santosh Kumar S1, Sujay V K1, a, Pavithra P2, Vittal B G3, Madhan Srinivasamurthy4, Yallappa B Saunshi4, Sunil C Aramani1, b
1Department of Forensic Medicine, 2Department of Community Medicine, 3Department of Biochemistry, 4Multi-disciplinary Research Unit,
Hassan Institute of Medical Sciences, Hassan, Karnataka, India
aDepartment of Forensic Medicine, Kasturba Medical College, Mangalore, Manipal Academy of Higher Education, Manipal, India.
bDepartment of Forensic Medicine, Haveri Institute of Medical Sciences, Haveri, Karnataka, India.
Corresponding Author: Sunil C Aramani
ABSTRACT
The biochemical analysis of vitreous humor provides a valuable approach to estimating the post-mortem interval (PMI). Following death, the vitreous humor undergoes predictable biochemical changes, making it a reliable substrate for temporal estimation. This study explores the relationship between PMI and the chemical constituents of vitreous humor, with particular emphasis on potassium and hypoxanthine (Hx).
The study involved a total of 55 medico legal autopsies. Vitreous humor samples were collected from all subjects and the experiments were conducted using the Ultra-Performance Liquid Chromatography (UPLC) technique and an electrolyte analyzer.
Hypoxanthine (Hx) levels increased significantly from 78.68 to 268.97 µmol/L across PMIs determined by police records and from 87.26 to 280.09 µmol/L by physical examination. The linear regression analysis of Hx levels concerning PMI from police records and physical examinations demonstrated a statistically significant correlation, with R2 values of 0.86 and 0.76, respectively. This suggests Hx as a more reliable PMI biomarker compared to potassium.
In contrast, potassium levels showed no statistically significant relationship with PMI based on either police records (p=0.688) or physical examination findings (p=0.806). The consistent and significant rise in Hx concentration with increasing PMI (p < 0.001) underscores its potential usefulness for estimating time since death. The study concludes that hypoxanthine concentration in vitreous humor serves as a more dependable indicator for PMI evaluation, whereas potassium contributes minimally to time-of-death estimation.
Key words: Hypoxanthine; Post-mortem interval; Potassium; UPLC; Vitreous humor