A polyaniline based ultrasensitive potentiometric immunosensor for cardiac troponin complex detection

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Cardiovascular Diagnostics

Background:

• Cardiac troponin I-T-C complex is a critical biomarker for diagnosing myocardial infarction.
• Existing detection methods often lack the required sensitivity, speed, or simplicity for point-of-care applications.

Purpose of the Study:

• To develop an ultrasensitive and rapid immunosensor for detecting cardiac troponin I-T-C complex.
• To utilize potentiometric ELISA with a novel transducer for enhanced signal detection.

Main Methods:

• Fabrication of a glassy carbon electrode modified with polyaniline/dinonylnaphthalenesulfonic acid (PANI/DNNSA) as a transducer.
• Implementation of a sandwich ELISA assay with horseradish peroxidase (HRP) labeled secondary antibodies.
• Signal readout via open circuit potentiometry (OCP) based on enzymatic reaction-induced potential changes.

Main Results:

• Achieved an ultrasensitive detection of troponin I-T-C complex with a low limit of detection (< 5 pg/mL).
• Demonstrated a wide dynamic range (> 6 orders of magnitude) and high repeatability (CV < 8%).
• The developed immunosensor provided results in a short detection time (< 10 min).

Conclusions:

• The developed potentiometric ELISA immunosensor is a highly sensitive and rapid tool for cardiac troponin I-T-C complex detection.
• The PANI/DNNSA transducer combined with OCP offers a promising platform for advanced electrochemical biosensing.
• This technology holds potential for improved early diagnosis of cardiac events.