Determination of lithium in the blood of the deceased by inductively coupled plasma mass spectrometry in a case of lithium-ion battery fire.

In this study, a case of lithium-ion battery fire is presented. The blood of the deceased was analyzed for lithium (Li) using ICP-MS (inductively coupled plasma mass spectrometry). When compared to normal individuals in the same region, the deceased had much higher levels of Li in their blood. Therefore, conducting quantitative analyses of Li in the bodies of individuals who die in lithium-ion battery fire can provide valuable information into the specific circumstances surrounding their deaths.

A highly efficient liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay for etomidate and etomidate acid in urine, liver and kidney.

Etomidate (ETO) is a highly-efficient drug that can induce anesthesia with increasing doses, thus subject to strict regulation. However, an accurate and efficient method for ETO intake detection is currently lacking. Therefore, this study developed a straightforward sample preparation method using LC-MS/MS to analyze ETO and its primary metabolite, etomidate acid (ETA), in urine, liver, and kidney samples. Snap frozen pig liver and kidney samples were ground into a fine powder. Then, all the biological samples, including human urine, pig liver and kidney tissues, were deproteinized using acetonitrile and filtered for analysis. The separation was achieved in 9.01 min with gradient elution. The calibration curves ranged from 0.5 to 50 ng/mL for ETO in urine and 0.5 to 50 ng/g in liver and kidney, while the curves ranged from 1 to 100 ng/mL for ETA in urine and 1 to 100 ng/g in liver and kidney. The correlation coefficients (R2) were greater than 0.9957. The Limit of detection (LOD) and limit of quantitation (LOQ) for ETO were 0.2 and 0.5 ng/mL in urine samples and 0.2 and 0.5 ng/g in liver and kidney samples, respectively. For ETA, the LOD and LOQ were 0.5 and 1 ng/mL in urine samples and 0.5 and 1 ng/g in liver and kidney samples. This method was assessed by validation parameters, including selectivity, intra- and inter-day precision and accuracy, recovery, matrix effect, dilution integrity and stability. It was successfully applied to a practical case, revealing ETO and ETA concentrations in urine of 1.01 and 5.58 µg/mL, in liver samples of 12.30 and 1.13 µg/g, and in kidney samples of 6.95 and 4.23 µg/g. This suggests that the method is suitable for routine forensic detection of illicit ETO abuse.