Blood microsampling,
without the venous draw.

The needle was
the bottleneck.

Clinic-and-needle dependency quietly caps everything downstream. It limits who enrols, how often you can sample, how diverse a cohort you can reach, and what each data point costs, and a large share of adults actively avoid blood draws. Capillary microsampling, patient-centric sampling in the industry’s own phrase, removes that ceiling.

Validated use is published across at-home HbA1c, pediatric pharmacokinetic sampling, therapeutic drug monitoring, anti-doping and decentralised clinical trials, and the papers are in the research library; remote programmes consistently report high sample-return compliance.

Most of the menu,
and what stays venous.

Honesty matters more than reach here. A large part of the routine catalogue is well-suited to validated capillary collection. A defined set of tests still belongs in a venous tube, and we say so up front.

Suitability is established per analyte through method validation before any patient-facing reporting; the table is a guide to where capillary is strong, not a substitute for an assay-level decision with your laboratory.

We chose VAMS.

Every dried-blood format has to answer one question: how much blood is actually in the sample the laboratory analyses. A classic spot leaves it uncontrolled; VAMS fixes it at source. Volumetric absorptive microsampling wicks a fixed, known volume of capillary blood onto an absorbent tip: a set 10 to 30 µL regardless of how the blood would spread, and largely independent of haematocrit. The whole tip is then analysed, so there is no sub-sampling and no spot-area bias. That is precisely what quantitation needs, which is why VAMS is our default dried-blood solution on the platform.

Introduced by Denniff and Spooner in 2014, VAMS is now one of the most actively validated microsampling techniques in bioanalysis, with a decade of peer-reviewed method and clinical validation behind it. The evidence is aggregated below →

Three ways to dry a sample.

All three dry the blood and ship it ambient. They differ in one thing, whether the volume analysed is controlled, and that difference decides which analytes each can quantify.

VAMS, the volumetric tip

The tip absorbs a fixed volume and is analysed whole, so the area-bias and homogeneity problems of a spot are removed by design. An honest nuance for method developers: removing the volumetric bias does not make every assay perfectly haematocrit-independent a residual, haematocrit-dependent recovery effect can persist for some analytes, so each assay is still validated per analyte rather than assumed. It is the format built for quantitation.

Dried blood spot, the proven classic

The dried blood spot is the original micro-volume format, and its pedigree is more than six decades deep: population newborn screening, tens of millions of infants a year, runs on it, and because immunoglobulins are stable when dried and serology reads a ratio rather than an absolute volume, DBS underpins large-scale antibody surveillance too. Its strengths are real. Its limitation is specific and narrow: getting an accurate concentration from a fixed sub-punch of a spot formed from an unknown volume, where the haematocrit effect, sub-punch variability and non-uniform analyte spreading all bear on the result. The card is excellent; the uncontrolled volume is the caveat. Because the dried matrix preserves nucleic acids at ambient temperature, a dried blood spot is also a stable source of genomic DNA: genotyping, pharmacogenomics and sample-identity checks run from a punched disc, and whole-genome sequencing has been achieved from archived newborn cards.

Quantitative DBS: the spot, upgraded

Quantitative DBS keeps everything patients and labs like about the card, finger-prick, dried paper, ambient post, and fixes the one weakness: it meters a precise, known volume onto the card and analyses the whole disc, so there is no sub-punch and no haematocrit-driven area bias. It is best understood not as a different sample type but as the dried blood spot done quantitatively: the classic card, with the volume brought under control.

Validated before it reports.

Because dried formats can carry haematocrit and recovery considerations, every panel is validated per analyte along a research-to-clinical transfer pathway into ISO 15189-accredited laboratories, both analytical validation and clinical validation against a venous reference. Where a plasma-equivalent result is reported from capillary blood, an established, analyte-specific capillary-to-plasma relationship is applied, following the IATDMCT guideline on capillary-to-plasma conversion. VAMS, the Neoteryx Mitra, is a CE-marked component within those validated kits.

The reference frameworks a laboratory implements against, the IATDMCT guidelines on dried-blood method validation and on capillary-to-plasma conversion, are listed in the reading below.

What is liquid
capillary collection?

Liquid capillary blood microsampling collects a small volume of whole blood from the upper arm or fingertip and keeps it in liquid form rather than drying it, so the sample reaches the laboratory intact. It is the family for assays that need the whole sample, and for downstream plasma separation. Because liquid blood is less stable than a dried sample, it travels stabilised and, where the assay requires, under controlled-temperature transport.

Where dried is the default, liquid is the managed exception, reserved for analytes that genuinely need an intact sample, and run through the same accredited-laboratory path under documented chain of custody.

Handled, where the assay requires.

A liquid sample is less forgiving than a dried one, so logistics does more of the work. Where the analyte allows, chemical stabilisation, preservatives, buffers and internal standards, protects the sample in transit. Where it doesn’t, controlled-temperature transport is orchestrated and temperature-logged from collection to accessioning.

Controlled-temperature transport is applied only where the assay requires it, never by default. See how we protect the sample →

From a fingertip
to a signed result.

A home-collected sample is only clinical-grade if it arrives as the sample the patient gave. Every step carries identity, integrity and a record, the audit trail that lets a result be trusted for a medical decision.

Humans Nexus integrates accredited laboratories; we never run, or compete with, a lab. We provide the regulated kit, the clinical-grade logistics and the software that connect the patient to the laboratory you already trust.

Good to know.