Magnetic Dendritic Polymer Nanospheres for High-Performance Separation of Histidine-Rich Proteins

Magnetic nanospheres are becoming a promising platformfor a widerange of applications in pharmacy, life science, and immunodiagnosticsdue to their high surface area, ease of synthesis and manipulation,fast separation, good biocompatibility, and recyclable performance.In this work, an innovative and efficient method is developed by insitu reducing and growing Ni(OH)(2) for the preparation ofdendritic mesoporous nanocomposites of silica@Fe3O4/tannic acid@nickel hydroxide (dSiO(2)@Fe3O4/TA@Ni(OH)(2)). The flower-like nanosphereshave good magnetic response, large surface area, and high histidine-richprotein (His-protein) purification performance. The dSiO(2)@Fe3O4/TA@Ni(OH)(2) nanospheres weresynthesized on the basis of a phi(NaSal/CTAB) of 1/1 and a massof ferrous chloride tetrahydrate of 0.3 g, resulting in a saturationmagnetization value of 48.21 emu/g, which means it can be collectedwithin similar to 1 min using a magnetic stand. Also, the BET test showedthat the surface area is 92.47 m(2)/g and the pore size is similar to 3.9 nm for dSiO(2)@Fe3O4/TA@Ni(OH)(2) nanocomposites. Notably, the nickel hydroxide with uniqueflower-like structural features enables the combination of a largenumber of Ni2+ ions and His-proteins for high performance.The isolation and purification experiments of the synthesized dSiO(2)@Fe3O4/TA@Ni(OH)(2) were performedby separating His-proteins from a matrix composed of bovine hemoglobin(BHb), bovine serum albumin (BSA), and lysozyme (LYZ). The resultshowed that the nanospheres have a high combination capacity of similar to 1880mg/g in a rapid equilibrium time of 20 min, which was selective forthe adsorption of BHb. In addition, the stability and recyclabilityof BHb are 80% after seven cycles. Furthermore, the nanospheres werealso used to isolate His-proteins from fetal bovine serum, provingits utility. Therefore, the strategy of separating and purifying His-proteinsusing dSiO(2)@Fe3O4/TA@Ni(OH)(2) nanospheres is promising for practical applications.

Automated summary

In this study, dendritic mesoporous nanocomposites of silica@Fe3O4/tannic acid@nickel hydroxide (dSiO(2)@Fe3O4/TA@Ni(OH)(2)) were successfully prepared by in situ reducing and growing Ni(OH)(2). The nanocomposites exhibited good magnetic response, large surface area, and high histidine-rich protein purification performance. The nanospheres showed high adsorption selectivity for bovine hemoglobin, and the stability and recyclability of the adsorbed protein were also good.