Nickel(II)-immobilized sulfhydryl cotton fiber for selective binding and rapid separation of histidine-tagged proteins

In the current study, a novel nickel(II)-immobilized sulfhydryl cotton fiber (SCF-Ni2+) was prepared in a simple way based on the coordination effect between Ni2+ and thiol group on the surface of SCF. The composition and element mapping of SCF-Ni2+ fibers were demonstrated by energy-dispersive X-ray (EDX) spectroscopy. Based on the high affinity of Ni2+ to 6 × His on histidine-tagged (His-tagged) proteins, SCF-Ni2+ fibers were then further used as an immobilized metal ion affinity chromatography (IMAC) adsorbent for selective binding and rapid separation of His-tagged proteins using an in- pipette-tip SPE format. Our results showed that SCF-Ni2+ adsorbent can selectively capture His-tagged proteins from protein mixture and Escherichia coli cell lysates. Taken together, the developed method provides a rapid, convenient and efficient approach for the purification of His-tagged proteins.