Capillary blood microsampling and LC-Orbitrap analysis for adherence monitoring of cardiovascular drugs: method development, cross-validation, and patient proof-of-concept using VAMS and Capitainer-B
Kretschmer et al.
The finding, in our words
This method validation for 15 cardiovascular drugs found that VAMS and Capitainer-B provided interchangeable patient results, although Capitainer-B showed higher matrix effects while VAMS exhibited stability losses for specific analytes after two weeks. The work confirms the suitability of these microsampling workflows for decentralised adherence monitoring but highlights the need for analyte-specific stability testing.
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 review found that volumetric microsampling devices, such as Mitra, HemaPEN, HemaXis DB10, and Tasso-M20, overcome haematocrit bias, whilst Telimmune plasma separation cards enable direct plasma collection without centrifugation. These technologies support patient-centric, decentralised sampling, though the authors note that clinical validation remains limited across different drugs and patient populations.
Huhn & Scherf-Clavel, Therapeutic drug monitoring (paywalled) · source ↗
The study compared quantitative dried blood spot (qDBS) and volumetric absorptive microsampling (VAMS) devices for measuring ganciclovir levels in capillary blood from pediatric renal transplant recipients. This comparison provides evidence for choosing between microsampling devices in therapeutic drug monitoring, supporting decentralised sampling approaches that reduce patient burden while maintaining analytical accuracy.
Kocur et al., European journal of pharmaceutical sciences : official journal of the European Federation for Pharmaceutical Sciences (paywalled) · source ↗
This study established conversion methods for estimating plasma concentrations from whole blood VAMS samples for seven out of ten oral anticancer drugs, finding good agreement between capillary and venous samples. Patients reported a positive experience with home sampling using this microsampling technique.
Meertens et al., Therapeutic drug monitoring · 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.