Cellulose aerogel regenerated from ionic liquid solution for immobilized metal affinity adsorption

•Cellulose aerogel regenerated from ionic liquid solution was prepared.•The aerogel exhibits a large surface area after introducing iminodiacetic acid.•Cu(II) was immobilized on the cellulose aerogel bearing iminodiacetic acid.•Immobilized metal affinity adsorption was conducted using the modified cellulose.•The Cu(II) immobilized cellulose showed a high adsorption capacity for proteins. Surface morphology of cellulosic adsorbents is expected to influence the adsorption behavior of biomacromolecules. In the present study, cellulose aerogel regenerated from ionic liquid solution was prepared for use as a polymer support for protein adsorption. Iminodiacetic acid groups were introduced to the aerogel for immobilized metal affinity adsorption of proteins. A Cu(II)-immobilized iminodiacetic acid cellulose aerogel (Cu(II)-IDA-CA), which has a large specific surface area, showed a higher adsorption capacity than Cu(II)-immobilized iminodiacetic acid bacterial cellulose (Cu(II)-IDA-BC) and Cu(II)-immobilized iminodiacetic acid plant cellulose (Cu(II)-IDA-PC). In contrast, the Cu(II)-immobilized cellulosic adsorbents showed similar adsorption capacities for smaller amino acid and peptides. The results show that cellulose aerogels are useful as polymer supports with high protein adsorption capacities.