The pandemic of COVID-19 respiratory disease in 2019 has increased the urgent need for an effective identification and screening method. Since, the disease includes several phases, biomarkers identification can aid the patient to predict the severity. It is unclear whether all asymptomatic patients produce measurable antibody titers indicative of infection, because the concentration of the biomarkers changes in different stages of disease. Identification of asymptomatic patients helps in the management and prevention of this pandemic. This work reports the application of micropreparative polyacrylamide gel electrophoresis (MP-PAGE) for the detection, separation, and extraction of COVID-19-specific antibodies (IgG and IgM) directly from human’s sera. Unlike conventional diagnostic methods, MP-PAGE is a label-free, cost-effective platform that enables both diagnostic identification and preparative purification of viral biomarkers with minimal sample processing. The method demonstrated high analytical sensitivity, achieving a limit of detection (LOD) of 0.07 mg/mL under optimized conditions. Distinct electropherogram profiles allowed for the identification of antibody responses in both symptomatic and asymptomatic individuals, addressing a critical gap in early and silent case detection. The diagnostic outcomes were validated against RT-PCR, showing strong concordance (κ = 0.72). Beyond its diagnostic utility, MP-PAGE enables the extraction of functional antibodies, supporting applications in therapeutic antibody development and vaccine monitoring. Its simplicity, low cost, and scalability make it particularly suitable for deployment in resource-limited settings, while its potential for miniaturization offers promise for point-of-care testing. This work positions MP-PAGE as a powerful, dual-purpose platform for serological analysis, with broad implications for pandemic response, biomedical research, and global health preparedness.

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