Detection of metformin in dried blood on cotton cloth using QuEChERS procedure and liquid chromatography-mass spectrometry (LC-MS)
Gomez, Nataly A.
MetadataShow full item record
The Dried Blood Spot method has recently gained popularity in drug toxicology and could also be used to test blood samples in the forensic field. Testing dried blood stains found at a crime scene can help an investigator reveal what a person has consumed and if it played a role in their behavior or cause of death. This study determined if analyzing a dried blood spot located on a cotton cloth could be an alternate source for obtaining a toxicological background. Although there are a few studies determining toxicological profiles on dried blood stains on cotton material, to our knowledge only a few have attempted to analyze the dried blood directly from cloth without putting preservatives on the blood, and none have used QuEChERS extraction. This experiment was accomplished using cloth that was saturated in pig blood and allowed to dry with different metformin (an anti-diabetic medication) concentrations and for different aging periods (1 to 4 months). Metformin was then extracted from the dried blood and analyzed by LC-MS. It was hypothesized that metformin would remain stable on the dried blood over the course of 4-months and that extraction and clean up by QuEChERS would be effective. The findings include that methanol was a better extraction solvent used among other solvents (methanol/water, methanol/acetonitrile, acetonitrile, and water/acetonitrile at 3:6 and at 1:6). It was determined that percent recovery of metformin using QuEChERS extraction was between 87% and 102% and that metformin remains stable in dried blood on cotton cloth for 4-months with no significant changes to its calculated concentration. The methodology used to test the dried blood samples could be applied across the forensic toxicology field to help discover, enhance, or support other found toxicant concentrations detected in the body by different means. This study has the potential to reveal if a victim or suspect in question was using legal or illegal pharmaceuticals by testing blood stains left at the scene of the crime.