Two porous aromatic frameworks with different porous structures for high-performance aptasensing penicillin G via differential pulse voltammetry.

This study presents the rational design and synthesis of two porous aromatic frameworks (PAFs) via covalent bond-coupled monomers using Friedel-Crafts alkylation. PAFs have abundant porous structures and extended π-conjugated networks for aptamer immobilization. Compared with PAF-naphthalene, PAF-pyrene possesses a higher specific surface area, larger pores, and a larger conjugated system, which makes it more conducive to loading more aptamers and obtaining a more sensitive electrochemical aptasensor. Penicillin G (PCL) is a widely used broad-spectrum antibiotic, which is selected to investigate the sensing ability of aptasensors. The electrochemical aptasensor based on PAF-pyrene can quantitatively detect trace PCL using differential pulse voltammetry (DPV), which exhibits a good linear range from 1.0 × 10-5 to 0.1 ng mL-1 with a low limit of detection (LOD) of approximately 0.067 pg mL⁻1. This work develops an available approach for constructing high-performance PAF-based electrochemical aptasensors and expands their applications in the electrical biosensing field by establishing a direct structure-property-performance correlation for aromatic building block selection.