Synergetic enhancement: Imprinted magnetic microspheres based on the thiol-ene-amine conjugation and metal coordination for selective recognition of BSA

The preparation of high-specific protein imprinted materials remains challenging for the huge size, structural complexity and conformational flexibility of proteins. To overcome these difficulties, this work put forward a novel dual protein-anchoring strategy toward bovine serum albumin (BSA) by integrating the thiol-ene-amine conjugation and metal coordination into one imprinting system. The 1-(3-aminopropyl)imidazole (API) was selected as a bridge to combine the Ni²⁺ coordination and thiol-ene-amine conjugation. Benefitting from the rational design, the dual protein-anchoring strategy achieved the synergy of thiol-ene-API conjugation and Ni²⁺ coordination owing to long anchoring segments and strong affinity to BSA. Therefore, the prepared protein imprinted microspheres exhibited satisfactory adsorption capacity (216.54 mg/g), excellent imprinting factor (6.12), and fast adsorption saturation kinetics (40 min), superior to our previous reports that only includes one of protein anchors. In addition, the imprinted microspheres also showed superb specificity not only in competitive protein samples but also in bovine serum. It is very promising for the materials in the field of detection and analysis of diseases.