New Interface for Purification of Proteins: One-Dimensional TiO2 Nanotubes Decorated by Fe3O4 Nanoparticles.

In this work, a high surface area interface, based on anodic one-dimensional (1D) TiO2 nanotubes homogeneously decorated by Fe3O4 nanoparticles (TiO2NTs@Fe3O4NPs) is reported for the first time for an unprecedented purification of His-tagged recombinant proteins. Excellent purification results were achieved from the model protein mixture, as well as from the whole cell lysate (with His-tagged ubiquitin). Compared to a conventional immobilized-metal affinity chromatography (IMAC) system, specific isolation of selected His-tagged proteins on behalf of other proteins was significantly enhanced on TiO2NTs@Fe3O4NPs interface under optimized binding and elution conditions. The combination of specific isolation properties, magnetic features, biocompatibility, and ease of preparation of this material consisting of two basic metal oxides makes it a suitable candidate for future purification of recombinant proteins in biotechnology. The principally new material bears a large potential to open new pathways for discoveries in nanobiotechnology and nanomedicine.