Two-dimensional paper chromatography-based fluorescent immunosensor for detecting acute myocardial infarction markers

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Immunosensor Technology

Background:

• Lateral flow assays often suffer from background noise, limiting diagnostic accuracy in complex biological samples like human serum.
• Accurate and rapid detection of cardiac biomarkers is crucial for diagnosing acute myocardial infarction (AMI).

Purpose of the Study:

• To develop a novel washing scheme for a fluorescent immunosensor to overcome background issues in lateral flow assays.
• To create an integrated immunosensor system for simultaneous detection of cardiac troponin I (cTnI), creatinine kinase-MB isoform (CK-MB), and myoglobin for AMI diagnosis.

Main Methods:

• Development of an immuno-membrane strip for multiplexed biomarker detection within a cartridge.
• Implementation of an automated, cross-flow washing system initiated by internal control signaling upon sample addition.
• Utilized two-dimensional chromatography principles for enhanced signal resolution and background suppression.

Main Results:

• The novel washing scheme significantly suppressed background noise, achieving a low detection limit for cTnI (0.05 ng/mL) with good reproducibility (RSD <10%).
• The system demonstrated no interference from complex formations or sample matrices, ensuring reliable measurements.
• High correlation coefficients (>0.98) were observed when comparing results with the Pathfast reference system for cTnI, CK-MB, and myoglobin.

Conclusions:

• The developed fluorescent immunosensor with an integrated washing system effectively resolves background problems in lateral flow assays.
• This technology offers a sensitive, reproducible, and reliable platform for simultaneous detection of key cardiac biomarkers, suitable for clinical diagnostics of acute myocardial infarction.