Lab-in-Syringe Automated Miniaturized Bioconjugation of Magnetic Beads with Anti-SARS-CoV2 Antibodies

We present the first automated synthesis of magnetic immunosorbents (MIS) using a lab-in-syringe (LIS) platform, facilitating antibody bioconjugation to magnetic beads via carbodiimide-mediated covalent binding. This approach is an efficient, reproducible alternative to traditional manual methods, minimizing pipetting steps, vortexing, and incubation with a reduced handling bias. Utilizing a 1 mL syringe pump with a 12-port multiposition valve and an internal magnetic stir bar enables precise mixing, bead dispersion, and magnetic capture for consistent bioconjugate synthesis. The LIS platform achieved a 99.6% bead recovery with 0.4 mg of MIS (1 μm in diameter), outperforming the 83% recovery of manual techniques, and maintained an 83% recovery at reduced scales of 0.2 mg, surpassing manual yields of 76%. As a proof-of-concept, MIS conjugated with anti-SARS-CoV2 antibodies (6 μg/400 mg beads) were synthesized and validated for viral RNA isolation from COVID-19-positive samples, demonstrating high immunocapture efficiency comparable to manual methods but with significantly reduced time and labor requirements. This automated synthesis of antibody-MIS enables the scalable, reproducible production of bioconjugated materials, supporting advanced applications in diagnostic assays, therapeutic delivery, and microfluidic integrations. The LIS approach thus enhances the scope of biomolecular conjugate synthesis, offering streamlined workflows that are suited for downstream analytical and bioanalytical applications. LIS is a versatile, automated system for preparing MIS that researchers can adapt for various targets, particularly when commercial products are unavailable, are prohibitively expensive, or require custom carriers.