Histidine-tagged enzyme conjugated heterogeneous magnetic mesoporous silica for high efficient biodegradation of catechol

In this study, we present a novel method for mesoporous silicas which are functionalized with Fe and Ni ion to support His-tagged proteins. Mesoporous silicas were combined with iron (II) chloride tetrahydrate for initiating magnetizing process, followed by reduction in H2 media. The nickel (II) chloride hexahydrate was introduced into pore and surface of heterogeneous magnetic mesoporous silicas (HMMS) by wet impregnation process. The resulting materials were reduced in a flowing of H2 at 500 °C for 2h, thereby producing Ni particles on the surface of the HMMS. The Ni-HMMS was characterized by various state-of-the-art techniques, such as WAXS, FE-SEM, TEM, SQUID and nitrogen sorption. Ni-HMMS showed high adsorption level of His-tagged protein from Escherichia coli lysate. In addition, the purified His6-CatA was observed high enzyme activity. It suggests that Ni-MMS system provides contribution for maintain stable protein structure as well as simplified protein purification process.