A new procalcitonin optical immunosensor for POCT applications

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Immunotechnology

Background:

• Procalcitonin (PCT) is a biomarker for bacterial infections and sepsis.
• Accurate and rapid PCT determination is crucial for timely clinical decisions.
• Existing diagnostic methods may lack the speed or sensitivity required for point-of-care settings.

Purpose of the Study:

• To develop a novel immunosensor for sensitive procalcitonin (PCT) determination.
• To implement a sandwich assay on an optical biochip for potential point-of-care testing (POCT).
• To evaluate the assay's performance in both buffer and human serum samples.

Main Methods:

• Development of a sandwich immunoassay using two rat monoclonal antibodies.
• Immobilization of a capture antibody onto a polymethylmetacrylate (PMMA) optical biochip with flow channels.
• Labeling of the detection antibody with DY647 fluorescent dye and optimization to minimize non-specific adsorption.

Main Results:

• Achieved a limit of detection (LOD) of 0.088 mg L⁻¹ within a working range of 0.28–50 mg L⁻¹ in buffer.
• Successfully adapted the assay for human serum samples.
• Attained an LOD of 0.2 mg L⁻¹ and a working range of 0.7–25 mg L⁻¹ in human serum.

Conclusions:

• The developed immunosensor demonstrates high sensitivity and a suitable working range for procalcitonin detection.
• The optical biochip platform is adaptable for point-of-care testing applications.
• This technology offers a promising tool for rapid and accurate procalcitonin diagnostics in clinical settings.