Volumetric dried blood spots for determination of phosphatidylethanol: Validation of a liquid chromatography tandem masspectrometry method and clinical application
Beck et al.
The finding, in our words
Volumetric dried blood spot sampling gave more precise phosphatidylethanol quantification than conventional cards in fingerprick blood (coefficient of variation 4.6% versus 16.6%). Capillary and venous dried spots produced identical results, validating the method for decentralised alcohol biomarker testing via postal transport.
A paraphrase to the Library’s standard, never the abstract. The source is one link away and is always the authority.
In AML and CLL, 91% of VAMS venetoclax results fell within 20% of plasma after individualised haematocrit correction; in home sampling, 18 of 21 patients self-sampled independently and 76% of returned samples were analysable, which shows home microsampling is workable, though the authors ask for multicentre validation.
Levens et al., Clinical Pharmacokinetics (paywalled) · source ↗
This study validated a method for measuring the alcohol biomarker phosphatidylethanol using two volumetric absorptive microsampling devices, finding that the Mitra device met all validation criteria and agreed with venous sampling. The Capitainer device was deemed suitable but showed reduced accuracy at higher concentrations, with a small proportional negative bias compared to venous results.
Andreassen et al., Journal of analytical toxicology (paywalled) · source ↗
A 2025 review maps 28 microsampling devices, from dried spots and volumetric absorptive tips to upper-arm liquid capillary collectors, and names what a laboratory must control before their results are used: the haematocrit effect in non-volumetric dried samples, interstitial fluid from finger milking, volume, haemolysis and transport stability. Regulators on both sides of the Atlantic ask for the same two things, a device the patient can use safely and a sample fit for the test.
LC-MS/MS measurement of imatinib and its active metabolite from volumetric dried blood spots collected via HemaXis DB10 and Capitainer B demonstrated analytical precision across hematocrits from 22% to 55% alongside 43-day ambient stability. Clinical evaluation across 52 paired samples showed high agreement with plasma concentrations, verifying both devices as reliable options for decentralised therapeutic drug monitoring.
Orleni et al., Journal of chromatography. B, Analytical technologies in the biomedical and life sciences (paywalled) · source ↗
An LC-MS/MS assay accurately quantified osimertinib and its active metabolites from volumetric dried blood spots collected with the hemaPEN device across a 30% to 60% haematocrit range. Drug levels in dried blood spots showed high concordance with plasma measurements in non-small cell lung cancer patients, with dried spots demonstrating superior room-temperature stability over ten days compared with plasma.
Venkatesh et al., Therapeutic drug monitoring · source ↗