Precision of the Abaxis VetScan VS2 for postmortem biochemical analysis of delphinid vitreous humor

Biochemical analysis of vitreous humor has several forensic applications, including toxicology, estimation of the postmortem interval, and as proxy for select antemortem serum analytes. Estimation of postmortem interval from vitreous humor analytes such as potassium has potential to be a valuable forensic tool for marine mammal strandings, as time of death is essential to provide spatial and temporal context for anthropogenic interactions. The Abaxis VetScan VS2 (VetScan) chemistry analyzer is inexpensive, compact, and requires low sample volume (100 μl), making it ideal for organizations with limited resources and limited samples. This pilot study compared accuracy of the Vetscan on delphinid serum/plasma (n = 7) to the Beckman Coulter AU480, validated the precision of the Vetscan for biochemical analysis of delphinid vitreous humor using the described sample processing protocol, and assessed analyte stability at room temperature in delphinid vitreous humor. Pooled samples (n = 12) of delphinid vitreous humor were serially analyzed and the between-run and within-run coefficient of variation of the VetScan was acceptable for most analytes tested but was not for creatinine, total bilirubin, amylase, and alanine aminotransferase. These results demonstrated the precision of the VetScan for the analysis of glucose, albumin, globulin, total protein, urea nitrogen, sodium, potassium, calcium, and phosphorus in delphinid vitreous humor.