Bioenzyme-induced molecularly imprinted polymers using optimal design of computational chemistry for enhanced specific electrochemical sensing of protocatechuic acid in medicines

The sensitive and selective determination of the active ingredient in medicines has become an inescapable challenge in the sensing field. With the concerns above, an electrochemical sensor has been designed based on theoretically optimized bioenzyme-induced molecularly imprinted polymers (MIPs) for the specific determination of protocatechuic acid (PA) for the first time. In detail, the LaFeO3 nanosphere is employed as the carrier to support bovine hemoglobin (BHb) and biomimetic enzyme Au nanoparticles, which can decompose hydrogen peroxide to generate hydroxyl radicals. These hydroxyl radicals can initiate polymerization to afford the optimized MIPs. More importantly, density functional theory based on computational chemistry is utilized to deduce the optimal functional monomer, resulting in the best recognition effect. Subsequently, the pre-fabricated electrochemical sensor based on LaFeO3 @Au@BHb-MIPs could achieve the specific determination of PA with a wide linear detection range of 0.2 μM to 1000 μM and the limit of detection of 55 nM. Meanwhile, the specific recognition of PA in traditional Chinese medicines such as hibiscus has been also accomplished with satisfactory recoveries, foreboding that the LaFeO3 @Au@BHb-MIPs is indeed a suitable candidate for monitoring medication safety.