Highly efficient porous magnetic polydopamine/copper phosphate with three-dimensional hierarchical nanoflower morphology as a selective platform for recombinant proteins separation.

The separation and purification of recombinant pharmaceutical proteins is a fundamental and challenging step in the biotechnology industry. Hierarchical nanostructures with unique features and high stability can be used as efficient adsorbents. In this study, hierarchical magnetic polydopamine-copper phosphate nanoflowers (Cu-PDA MNFs) were synthesized as high-performance magnetic adsorbents in a simple and low-cost method based on green chemistry. The prepared hybrid Cu-PDA MNFs revealed great performance for separating pure recombinant human growth hormone (rhGH) and the rhGH acquired from recombinant Pichia pastoris yeast fermentation. The analysis confirmed that Cu-PDA MNFs exhibited a high adsorption capacity of 257.4 mg rhGH g Cu-PDA MNFs and a fast adsorption rate for approaching the adsorption equilibrium within less than 30 min with a recovery efficiency of 74% of rhGH from the real sample. In addition, recycling tests demonstrated the stability and recyclability of Cu-PDA MNFs for at least six cycles with almost constant adsorption capacity and no toxicity. Based on these results, Cu-PDA MNFs could be considered as a promising candidate for separation and purification of rhGH. This work presents a new approach to using organic-inorganic nanoflowers as the hierarchical nanostructure for purification of pharmaceutical proteins with high performance.