Connecting the Dots: Bridging Microsamples and Conventional Blood Matrices in Metabolic Biomarker Analysis
Thaitumu et al.
The finding, in our words
This review evaluates the analytical agreement between blood microsamples and conventional liquid blood, plasma, or serum matrices across targeted and untargeted metabolomic profiling. It highlights haematocrit effects and the analytical validation required to support clinical adoption of patient-centric microsampling.
A paraphrase to the Library’s standard, never the abstract. The source is one link away and is always the authority.
A dried blood spot microsampling method measuring over 400 metabolites showed 40% signal loss in the first three months but remained stable thereafter for at least one year when stored at -80°C with desiccants. The method was insensitive to haematocrit between 31-50% and blood volumes above 60 µL, and was clinically validated for diagnosing MELAS, offering a practical alternative to liquid blood for decentralised metabolomic studies.
Capillary dried blood spots, after haematocrit-dependent conversion, showed good agreement with plasma for 25-hydroxyvitamin D quantification, with 90 per cent of results within 20 per cent of plasma and substantial to almost perfect agreement in status classification, supporting reliable home self-collection for large-scale vitamin D monitoring.
Heughebaert et al., Clinical chemistry and laboratory medicine (paywalled) · source ↗
Capillary finger-stick dried blood spots demonstrated strong analytical agreement with venous serum for prostate-specific antigen (R² = 0.987) and remained stable for 31 days across a wide temperature range. This less invasive microsampling approach enables at-home self-collection, supporting decentralised screening and tele-diagnostics for prostate cancer.
van Vugt et al., The journal of applied laboratory medicine (paywalled) · source ↗
A comparison of three patient-centric dried blood microsampling devices, paper DBS, Mitra and Tasso-M20, found strong to excellent correlation with traditional venous plasma for measuring branched-chain amino acids and ketoacids. Participants reported high acceptability and expressed a strong willingness to use these devices for decentralised self-collection.
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.