An automated ELISA system using a pipette tip as a solid phase and a pH-sensitive field effect transistor as a...

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Immunodiagnostics

Background:

• Enzyme-linked immunosorbent assays (ELISA) are crucial for detecting biomarkers.
• Current ELISA methods can be time-consuming and labor-intensive.
• Need for automated, high-throughput diagnostic platforms.

Purpose of the Study:

• To develop a fully automated ELISA system.
• To utilize a pipette tip as a solid phase and urease as a detecting enzyme.
• To integrate a pH-field-effect transistor (pH-FET) for sensitive urease activity detection.

Main Methods:

• Constructed an automated ELISA system using a pipette tip as the solid phase.
• Employed urease as the enzyme label and a pH-FET as the detector.
• Integrated disposable reagent cartridges and automated pipetting for sample dilution and B/F separation.
• Applied the system to various immunoassay formats, including sandwich and competition assays.

Main Results:

• Achieved full automation of the ELISA process.
• The system demonstrated a throughput of 60 samples per hour.
• Assay time was reduced to 21 minutes for all configurations.
• Successfully applied to detect Alpha-fetoprotein (AFP), Carcinoembryonic antigen (CEA), Hepatitis B surface antigen (HBsAg), Hepatitis B surface antibody (HBsAb), Hepatitis B core antibody (HBcAb), and Human T-lymphotropic virus type 1 antibody (HTLV-I Ab).

Conclusions:

• The developed automated ELISA system offers a rapid and efficient platform for biomarker detection.
• The integration of a pipette tip solid phase and pH-FET detection enhances assay performance.
• This automated system has broad applicability in clinical diagnostics and research.