A Novel Dry-Stabilized Whole Blood Microsampling and Protein Extraction Method for Testing of SARS-CoV-2 Antibody Titres

Abstract

The COVID-19 pandemic has revealed a crucial need for rapid, straightforward collection and testing of biological samples. Serological antibody assays can analyze patient blood samples to confirm immune response following mRNA vaccine administration or to verify past exposure to the SARS-CoV-2 virus. While blood tests provide vital information for clinical analysis and epidemiology, sample collection is not uncomplicated. This process requires a visit to the doctors office, a professionally trained phlebotomist to draw several milliliters of blood, processing to yield plasma or serum, and necessitates appropriate cold chain storage to preserve the specimen. The Covaris truCOLLECT Whole Blood Collection Kit allows for a lancet-based, decentralized capillary blood collection of exactly metered low volumes and eliminates the need for refrigerated transport and storage through the process of active desiccation. Anti-SARS CoV-2 spike and nucleocapsid protein antibody titers in plasma samples collected via venipuncture were compared to antibody titers in whole blood extracts obtained by treating desiccated whole blood samples stored in truCOLLECT sampling devices with Covaris Adaptive-focused Acoustics (AFA). Pearson correlation coefficients of 0.98, 95% CI [0.96, 0.99] for anti-SARS-CoV spike protein antibodies and 0.97, 95% CI [0.94, 0.99] for anti-SARS-CoV-2 nucleocapsid protein antibodies were observed. These data suggest that serology testing using desiccated whole blood samples collected and stored in truCOLLECT devices can be a convenient and cost-effective alternative to conventionally collected plasma.