Clinical sensitivity and specificity of a high-throughput microfluidic nano-immunoassay combined with capillary blood microsampling for the identification of anti-SARS-CoV-2 Spike IgG serostatus
Michielin et al.
The finding, in our words
In participants 11 months after SARS-CoV-2 infection, the nano-immunoassay achieved 98.33% sensitivity and 97.62% specificity on venous serum. When combined with dried capillary microsampling, sensitivity was 95.05% with Mitra, 61.11% with repurposed glucose strips and 83.16% with HemaXis (91.49% after automated extraction), with no loss of specificity, supporting home-based sampling for serology.
A paraphrase to the Library’s standard, never the abstract. The source is one link away and is always the authority.
Capillary samples collected using dried blood spots and Mitra microsamplers showed strong agreement with venous plasma for quantifying IgG antibodies against most vaccine-preventable diseases. Sensitivity was high for the majority of pathogens, though the study noted that antibody stability declined at room temperature over time, favouring cold storage for longer durations.
The study found very strong correlation between venous blood collection and capillary VAMS using Mitra devices for detecting SARS-CoV-2 spike antibodies, with samples remaining stable at room temperature for several months. This enables reliable at-home, patient-centric serological testing for large-scale community surveillance and vaccine studies.
Capillary blood collected by fingerstick with the Mitra volumetric absorptive microsampling device showed near identical sensitivity and specificity for SARS-CoV-2 antibodies compared with venous serum when analysed with the Roche Elecsys assay. This validation enables decentralised, patient-centric serology testing for remote or at-home use and large-scale community seroprevalence studies.
VAMS capillary blood showed strong agreement with venous serum for measuring anti-influenza antibodies and remained stable for three weeks at room temperature. When volunteers performed finger-stick sampling at home, their results were highly consistent with on-site collection by study personnel.
In matched clinical samples from rheumatoid arthritis, VAMS and DBS showed strong agreement for methotrexate polyglutamates (slopes 0.95-1.07; bias within -4.21% to 0.36%; SRCC ≥ 0.969), with up to 100% of total MTXPG results within ±20% limits; capillary microsampling agreed closely with whole blood but differed from red blood cells, indicating matrix-specific differences that must be accounted for when interpreting against RBC-based reference values.