Paper-based multi-well depletion ELISA

Area of Science:

• Biotechnology
• Immunology
• Medical Diagnostics

Background:

• Enzyme-linked immunosorbent assay (ELISA) is crucial for detecting molecules in bioassays, including antibody titers.
• Traditional ELISA requires trained personnel and multiple manual steps in centralized labs.
• Current methods are time-consuming and labor-intensive, limiting accessibility.

Purpose of the Study:

• To develop an automated, instrument-free dipstick ELISA for rapid and accessible titer measurement.
• To overcome the limitations of conventional, multi-step laboratory-based ELISA procedures.
• To create a digital readout assay that eliminates the need for external equipment or specialized operators.

Main Methods:

• Developed a dipstick ELISA incorporating a flow controller for automated reagent delivery and sequential steps.
• Implemented an immuno-depletion process to measure analyte titer by gradually removing the target from a flowing sample.
• Applied the technology to quantify severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody titers and troponin I levels.

Main Results:

• Successfully automated the laborious ELISA workflow into a simple dipstick format.
• Achieved digital titer reporting without requiring external instruments or trained operators.
• Demonstrated the assay's versatility by developing tests for SARS-CoV-2 antibodies and troponin I.

Conclusions:

• The novel dipstick ELISA offers a simplified, automated, and accessible method for measuring molecular titers.
• This technology has the potential to decentralize diagnostic testing, making it more widely available.
• The assay is adaptable for various biomarkers, including viral antibodies and cardiac markers.