Sponges with large protein adsorption capacity are highly desired in various fields such as biosensors, biofuel cells, biocatalysis, and protein chromatography. However, the use of environmentally friendly materials and mass production still face enormous challenges. Herein, a novel and facile method to fabricate an environmentally friendly monolithic cellulose/chitosan composite sponge (CECSS) with remarkable performance is designed using the mature viscose process. The obtained highly efficient adsorption sponge exhibits a hierarchical porous structure with open-pore structures with a diameter range of 200–1000 μm and small micro/nanocellular structures (0.5–2 μm), which endow it with remarkable porosity (62.95%) and water adsorption capacity (1409%). Based on the abovementioned unique porous structure and reactive groups of chitosan, the CECSS exhibits a high bovine serum albumin adsorption capacity of 200.56 mg/g at pH 5.5 for 10 h. In addition, the adsorption of the CECSS can be well described by the pseudo-second-order kinetic model and the Langmuir isotherm model. This work provides a new sponge-forming process for the fields of protein adsorption, which may achieve the production of natural protein adsorbents at the industrial level.
Mengnan Qu,Yajie Pang,Jiehui Li,Rong Wang,Dan He,Zhanxia Luo,Fan Shi,Lei Peng,Jinmei He
Smart materials with controllable wettability have become one of the current research hotspots. Among them, the pH-responsive superwetting material is considered an ideal material because of its rapid response process and simple response mechanism. However, the pH-responsive materials reported previously could only perform wettability conversion in a single direction. In order to meet the demands of practical applications, it is indispensable to prepare the pH-bidirectional responsive superwetting material which can flexibly transform wettability in both directions. Based on this, a fluorine free and eco-friendly superwetting fabric with pH-bidirectional responsiveness was prepared by free radical polymerization and the combination of micro-nano hierarchical structure. A series of test results verified that the prepared fabric possessed excellent mechanical durability and chemical stability, satisfactory flux and separation efficiency. In addition, this work also successfully employed the prepared pH-bidirectional responsive superwetting fabric to realize the separation of three-phase oil-water-oil mixture. Surprisingly, the prepared fabric was also proved to be effective for the separation of multiple organic components, which was rarely reported in previous researches. Therefore, such pH-bidirectional responsive superwetting fabric will have broad application prospects in the field of oil-water separation and multi-organic components separation under the actual complex environment.