Multilayered Mesoporous Composite Nanostructures for Highly Sensitive Label-Free Quantification of Cardiac Troponin-I

Area of Science:

• Nanomaterials Science
• Biomedical Engineering
• Analytical Chemistry

Background:

• Cardiac troponin-I (cTnI) is a critical biomarker for diagnosing acute myocardial infarction.
• Existing electrochemical immunosensors require enhanced accuracy and reliability for clinical application.

Purpose of the Study:

• To develop a novel multilayer nanostructure for a highly sensitive and reliable cTnI electrochemical immunosensor.
• To improve the diagnostic capabilities for acute myocardial infarction through advanced biosensing technology.

Main Methods:

• Fabrication of a multilayer nanostructure using Fe3O4-COOH labeled anti-cTnI antibody (Fe3O4-COOH-Ab1) and anti-cTnI antibody (Ab2) conjugated on gold-silver (Au-Ag) nanoparticles decorated on a metal-organic framework (ZIF-67).
• Utilized Fe3O4-COOH for specimen separation and signal amplification.
• Employed hierarchical porous ZIF-67 for enhanced surface area and Au-Ag nanoparticles for improved conductivity and sensitivity.
• Characterized the nanostructure using electron microscopy.
• Evaluated immunosensor performance using electrochemical assays, including square wave voltammetry.

Main Results:

• Electron microscopy confirmed uniform decoration of Au-Ag nanoparticles (1.9 ± 0.5 nm) on ZIF-67 particles (690 nm) without agglomeration.
• The optimized immunosensor demonstrated high sensitivity (0.98 mA mL cm-2 ng-1) and a low detection limit (0.047 pg mL-1).
• The linear detection range was established from 0.04 to 8 ng mL-1 using square wave voltammetry.

Conclusions:

• The developed multilayer nanostructure provides a robust platform for sensitive and reliable cTnI detection.
• This advanced electrochemical immunosensor shows significant potential for improving the diagnosis and management of acute myocardial infarction.