UCT’s Refine™ ultra-filtration columns assessed for sample preparation in the determination of methylmercury and inorganic mercury species in whole blood

Biomonitoring measures the amount of a chemical substance and its metabolites in biological samples. It can be used to assess the bioavailability and exposure of humans and other animals to these chemicals. For example, prolonged mercury exposure can result in adverse effects on the central nervous and renal systems. Different species of mercury have different effects and toxicity on the human body. For faster and more sensitive detection of inorganic mercury, methylmercury, and ethylmercuary in whole blood Pacer et al developed an analytical method using liquid chromatograpy vapor generation inductively coupled plasma tandem mass spectrometry (LC-VG-ICP-MS/MS). 

250 µL of blood was aliquoted into a 15 mL polypropylene test tube with 4.75 mL of 0.1% tetramethylammonium hydroxide (TMAH) in deionized water. Samples were sonicated for 15 minutes and centrifuged before filtration. UCT’s 10 mL Refine^TM ultra-filtration columns were assessed alongside disposable 0.45 µm polyethersulfone (PES) filters for filtration of extracted samples. 

Samples prepared using Refine^TM ultra-filtration column and PES filters resulted in similar recoveries and analytical performance. It was observed that when samples were prepared using the Refine^TM ultra filtration columns, the guard column needed to be changed more frequently compared to when samples were prepared using PES filters. However, Refine^TM offers faster sample preparation as 48 samples can be simultaneously filtered using UCT’s positive pressure manifold.

Furthermore, the study optimizes analytical conditions and shows that the method’s sensitivity improves when vapor generation is utilized after liquid chromatography. Method limit of detection for mercury species in whole blood by LC-VG-ICP-MS/MS were 0.22 µg/L for inorganic mercury, 0.23 µg/L for methylmercury, and 0.33 µg/L for ethylmecury.  

Reference:Pacer, E. J., Palmer, C. D., & Parsons, P. J. (2025). A rapid method for the determination of methylmercury and inorganic mercury species in whole blood by liquid chromatography with detection using vapor generation ICP-MS/MS. Analytical Methods: Advancing Methods and Applications, 17(3), 456–465. https://doi.org/10.1039/D4AY02116A​