Dual Signal-Enhanced Electrochemiluminescence Strategy Based on Functionalized Biochar for Detecting Aflatoxin B1

Area of Science:

• Electrochemistry
• Materials Science
• Nanotechnology

Background:

• Metal-organic frameworks (MOFs) are effective carriers for electrochemiluminescent (ECL) materials.
• Encapsulating chromophores within MOFs enables aqueous-phase stabilization of ECL materials.
• MIL-88B(Fe)-NH2 MOFs offer abundant amino groups and pores, enhancing ECL efficiency.

Purpose of the Study:

• To prepare MIL-88B(Fe)-NH2@Ru(py)32+ nanocomposites for improved ECL response.
• To develop a dual signal-enhanced ECL immunosensor for sensitive and selective aflatoxin B1 (AFB1) detection.
• To utilize aminated biochar and gold nanoparticles as co-reactant promoters.

Main Methods:

• One-step hydrothermal synthesis of MIL-88B(Fe)-NH2@Ru(py)32+ nanocomposites.
• Preparation of aminated biochar from Pu-erh tea dregs.
• Loading gold nanoparticles onto aminated biochar.
• Fabrication of a sandwich-type ECL immunosensor.

Main Results:

• The MIL-88B(Fe)-NH2@Ru(py)32+ nanocomposites exhibited excellent ECL response.
• Aminated biochar and gold nanoparticles effectively promoted the K2S2O8 activation.
• The developed immunosensor achieved sensitive AFB1 detection in the range of 1 pg·mL−1 to 100 ng·mL−1.
• A low detection limit of 209 fg·mL−1 for AFB1 was obtained.

Conclusions:

• The dual signal-enhanced ECL immunosensor provides a highly sensitive and selective method for AFB1 detection.
• The proposed sensor is simple, convenient, and efficient for analyzing AFB1 in food and agricultural products.
• This work highlights the potential of MOF-based nanocomposites and biochar-derived materials in ECL sensing applications.