Submicro-Nano-Structured Cellulose Fibrous Membranes for High-Performance Protein Adsorption

Abstract

Fabricating simple and efficient protein adsorbents is crucial for meeting the demand for high-purity proteins, but it remains a long-standing challenge in biopharmaceutical and biotechnology industries. Herein, we developed submicro-nano-structured cellulose fibrous membranes (SNSCFMs) by combining the fine scale of carboxylated cellulose nanofibers (CNF–C) with the favorable structure of electrospun fibrous membranes. The incorporation of CNF–C created a hierarchical structure, resulting in a larger specific surface area, abundant active adsorption sites, and enhanced mechanical strength, thus endowing the SNSCFMs with high protein adsorption performance, which achieved a static capacity of 290.5 mg·g–1 for lysozyme (nearly 2.5 times that of the membrane without CNF–C loading), along with good selectivity and reusability. Moreover, a dynamic saturated adsorption capacity of 206 mg·g–1 was maintained under a pressure drop of 277 Pa. Meanwhile, this membrane successfully extracted lysozyme directly from fresh egg whites with a capacity of 136.2 mg·g–1, indicating promising potential for practical application. It is envisioned that such submicro-nano-structured cellulose fibrous membranes will provide a design paradigm for highly purified protein products.