Validating blood microsampling for per- and polyfluoroalkyl substances quantification in whole blood

• Published in: Journal of Chromatography A 2024-01, Vol.1713, p.464522, Article 464522
• Main Authors: Partington, Jordan M., Marchiandi, Jaye, Szabo, Drew, Gooley, Andrew, Kouremenos, Konstantinos, Smith, Fraser, Clarke, Bradley O.
• Format: Article
• Language: English
• Subjects: Analytical chemistry; Dried blood spot (DBS); Microsampling; Per-and polyfluoroalkyl substances (PFAS); Sample preparation
• ISSN: 0021-9673; 1873-3778
• DOI: 10.1016/j.chroma.2023.464522

Microsampling allows the collection of blood samples using a method which is inexpensive, simple and minimally-invasive, without the need for specially-trained medical staff. Analysis of whole blood provides a more holistic understanding of per- and polyfluoroalkyl substances (PFAS) body burden. Capillary action microsamplers (Trajan hemaPEN®) allow the controlled collection of whole blood as dried blood spots (DBS) (four 2.74 µL ± 5 %). The quantification of 75 PFAS from DBS was evaluated by comparing five common extraction techniques. Spiked blood (5 ng/mL PFAS) was extracted by protein precipitation (centrifuged; filtered), acid-base liquid-liquid extraction, trypsin protease digestion, and weak anion exchange (WAX) solid-phase extraction with analysis by high-performance liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). Filtered protein precipitation was the most effective extraction method, recovering 72 of the 75 PFAS within 70 to 130 % with method reporting limit (MRL) for PFOS of 0.17 ng/L and ranging between 0.05 ng/mL and 0.34 ng/mL for all other PFAS. The optimised method was applied to human blood samples to examine Inter- ( n = 7) and intra-day ( n = 5) PFAS blood levels in one individual. Sixteen PFAS were detected with an overall Σ 16 PFAS mean = 6.3 (range = 5.7–7.0) ng/mL and perfluorooctane sulfonate (branched and linear isomers, ΣPFOS) = 3.3 (2.8–3.7) ng/mL being the dominant PFAS present. To the authors knowledge, this minimally invasive self-sampling protocol is the most extensive method for PFAS in blood reported and could be a useful tool for large scale human biomonitoring studies.