Validation of a Dried Blood Spot Assay for Testosterone Measurement Using Liquid Chromatography-Tandem Mass Spectrometry
Gruenstein
The finding, in our words
A dried blood spot LC-MS/MS assay for testosterone was validated against venous serum, showing excellent linearity, precision below ten percent, and a lower limit of quantification of 0.086 ng/mL. Haematocrit correction was applied, and the strong clinical correlation supports decentralised hormone monitoring via finger-prick collection.
A paraphrase to the Library’s standard, never the abstract. The source is one link away and is always the authority.
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.
This study found that dried blood spot samples stored at room temperature for four years correlated highly with serum measurements for testosterone and androstenedione, indicating that hematocrit adjustment may be unnecessary for serial monitoring in home-based self-sampling.
Desai et al., The Journal of steroid biochemistry and molecular biology (paywalled) · source ↗
Capillary finger-stick dried blood spots yielded TSH measurements that agreed strongly with venous plasma (R² 0.988) and correctly identified hypothyroidism and hypothyrotropinemia in most cases. The analyte remained stable for at least four days between -20°C and +30°C, indicating potential for at-home collection in thyroid diagnostics and monitoring.
Schakelaar et al., Thyroid : official journal of the American Thyroid Association (paywalled) · source ↗
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 ↗
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 ↗