Wireless Graphene-Based Magnetoelastic Biosensor for COVID-19 Antibody Detection

High Resolution Image Download MS PowerPoint Slide This work presents a graphene-based magnetoelastic (ME) biosensor platform for wireless antibody detection via magnetoelastic resonance. Graphene was chosen for its biocompatibility and high surface area, enabling efficient antigen adsorption, validated by techniques such as EDX, AFM, and micro-Raman. Changes in Raman bands (a ∼10 cm −1 shift in the 2D band and an increase in the I D / I G ratio from 0.03 to 0.60) indicate non-covalent interactions and suggest enhanced surface coverage with 100 µg of N-nucleocapsid phosphoprotein. Tests using human plasma (10 RT-PCR-positive and 10 negative samples) demonstrated clear distinction between groups using graphene sensors functionalized with 100 µg of N-nucleocapsid phosphoprotein. The same result of ELISA validation, showing 100% sensitivity and specificity. The improvement in the performance of the graphene-based ME biosensor scales with surface biofunctionalization, which is performed effectively and reproducibly, as a result of assays on the optimization of protein concentration and biofunctionalization time. The platform combines graphene’s advantages with the wireless, real-time detection capabilities of ME biosensors, demonstrating potential for future low-cost and portable point-of-care diagnostic applications.