Multi-stimuli responsive molecularly imprinted nanoparticles with tailorable affinity for modulated specific recognition of human serum albumin

A kind of novel multi-stimuli responsive molecularly imprinted polymers with bovine serum albumin (BSA) as a dummy template (MSR-BSA-MIPs) was fabricated for specific recognition of human serum albumin (HSA) with modulated affinity. The MSR-BSA-MIPs were prepared through free radical polymerization using vinyl modified magnetic nanoparticles as substrates, bovine serum albumin (BSA), with high amino acid sequence similarity but low price compared to HSA, as the dummy template, N-(3-(dimethylamino)-propyl)-methacrylamide (DMAPMA) and N-isopropylacrylamide (NIPAm) as functional monomers with ionic strength and temperature response. The conditions of polymerization, adsorption and elution were systematically investigated. As expected, the obtained MSR-BSA-MIPs exhibited rapid dispersion or separation states under magnetic control, flexible conversion of adsorption and desorption for the target protein under temperature or ionic strength adjustment. Ten adsorption-desorption cycles were carried out with a little decrease in adsorption capacity under two different elution methods, which also inspired us to combine two elution methods while considering both the stability and adsorption capacity of MSR-BSA-MIPs. The adsorption capacity (Q) and imprinting factor (IF) of MSR-BSA-MIPs for HSA are 43.01 mg g⁻¹ and 4.26, respectively. Furthermore, the blood was opted as a realistic specimen for evaluating the adsorption capability of the proposed adsorbent, emphasizing its good practicality for target protein recognition and enrichment.