A Novel Metal Adsorbent Composed of a Hexa-histidine Tag and a Carbohydrate-binding Module on Cellulose

Anal Sci. 2020 Apr 10;36(4):459-464. doi: 10.2116/analsci.19P356. Epub 2019 Dec 20.


We developed a novel metal adsorbent composed of bio-based materials, cellulose and a protein. The approach involved the immobilization of a hexa-histidine tag (His6), which shows an affinity for an intermediate acid (metal ion) in Hard and Soft Acids and Bases (HSAB) theory, on cellulose by fusing with a carbohydrate-binding module (CBM). The results show that CBM-His6-bound cellulose has adsorption selectivity reflecting the original properties of His6. Additionally, we prepared three configurations of CBM-His6 proteins, which were subsequently immobilized on filter paper for Ni2+ ion adsorption. Of these configurations, we found that the protein containing two His6 tags at each terminus (N- and C-) of CBM exhibited the highest metal adsorption ability. Furthermore, XPS analysis confirmed the binding of Ni2+ ions on the cellulose.

Keywords: Carbohydrate-binding module; immobilization; metal affinity tag; transition metals.

MeSH terms

  • Adsorption
  • Binding Sites
  • Carbohydrates / chemistry*
  • Cellulose / chemistry*
  • Histidine / chemistry*
  • Nickel / chemistry*
  • Particle Size
  • Proteins / chemistry
  • Surface Properties


  • Carbohydrates
  • Proteins
  • Histidine
  • Nickel
  • Cellulose