In this paper, BSA surface-imprinted magnetic Fe-Ni bimetallic oxide shell nanorods (m-FeNi@MIPs@PCBMA) were prepared with the assistance of poly(3-[[2-(methacryloyloxy)ethyl]dimethylammonium] propionate (PCBMA) in connection with the surface-imprinting technique. The Fe-Ni bimetallic oxide shell layer nanorods (m-FeNi) with magnetic responsiveness simplified the separation and recovery process of adsorbed materials. The controlled introduction of PCBMA facilitated the reduction of protein non-specific adsorption. At the optimal encapsulation ratio of 1:0.75 (Wm-FeNi@MIPs: WCBMA), m-FeNi@MIPs@PCBMA could adsorb 122.98 ± 5 mg/g of BSA within 80 min, and the value of the imprinting factor (IF) was also increased from 1.68 (m-FeNi@MIPs) to 3.95. In the mixed protein adsorption and real sample separation experiments, m-FeNi@MIPs@PCBMA could selectively separate BSA. Meanwhile, after seven adsorption-desorption experiments, the loss of BSA adsorption by the imprinted nanorods was only 15.9%, which had good reusability. Therefore, m-FeNi@MIPs@PCBMA has a broader application prospect in the field of protein separation and purification.

Inspired by the stable interactions between metal ions and proteins, high external surface iron-nickel double hydroxides (Fe-Ni LDH) derived from metal-organic framework (MOFs) was selected as carriers to develop high performance surface bovine serum albumin (BSA) imprinted iron-nickel double hydroxides nanorods (Fe-Ni LDH@MIP). A hexagonal hollow structure Fe-Ni LDH was synthesized with nanosheets stacked on the surface by etching MIL-88A with Ni2+. The etching of Ni2+ increased the surface roughness of MIL-88A and the rough surface of the carrier was conducive to improving the anchorage amount of BSA, thus providing more effective imprinting sites. Controlled coating of the imprinted polymer layer on the surface of Fe-Ni LDH was obtained by aqueous phase precipitation polymerization. The protein adsorption amount reached to 329.8 ± 7.8 mg/g in 60 min with an imprinting factor of 2.86. The experimental showed that Fe-Ni LDH@MIP had good selectivity and stability, which enriched the protein imprinting materials.

Molecular imprinting technology has gained increasing attention and application in protein adsorption and separation. Bacterial growth on the imprinted material would reduce the adsorption selectivity of the imprinted cavity, contaminate the isolation products and shorten the service life of the material. To solve the above problems, carrier materials with dual antibacterial ability are constructed for the first time and novel surface protein imprinted microspheres (GO-PEI/MXene@MIPs) are manufactured. Thanks to the large exterior surface area, the saturation adsorption amount of GO-PEI/MXene@MIPs reaches 312.63 mg/g with an imprinting factor (IF) value of 3.16 within 90 min. Meanwhile, this imprinted material also exhibits a high ability to separate real samples as well as reusability. In addition, this material has excellent broad-spectrum antibacterial effects, which will significantly extend its service life in real-world environments. This study provides a feasible solution for the application of surface protein imprinted materials in real-world environments.

At present, the development of high-performance protein imprinted materials is still a research hotspot in the field of protein imprinting. Herein, anti-protein adsorption segment (CBMA)-assisted self-driven BSA surface imprinted fibers MTCFs@SIP@CBMA with high recognition selectivity are pioneered using the strategies of combining magnetic nanomaterial surface imprinting technique with amino-Michael addition. The special structure of the carrier MTCFs endows MTCFs@SIP@CBMA with magnetic performance and self-driven adsorption performance, which simplifies the separation process while improving the adsorption capacity and accelerating the adsorption rate. The adsorption capacity for BSA reached 395.26 mg/g within 30 min. The introduction of CBMA segments on the surface after imprinting by amino-Michael addition makes its polymer chain length and position controllable. Under the strongest anti-nonspecific adsorption effect, MTCFs@SIP@CBMA exhibit excellent specific identification to BSA from mixed proteins. Additionally, MTCFs@SIP@CBMA show considerable reusability. Therefore, MTCFs@SIP@CBMA are expected to be applied in efficient separation of proteins in biological samples.