Facile synthesis of new periodic mesoporous organosilica and its performance of immobilizing horseradish peroxidase

A new class of periodic mesoporous organosilicas (PMOs), which contains various hydrophilic groups of –OH, –O– and –S–, is successfully synthesized with novel bridged organosilica precursor under the acid-catalyzed and inorganic-salt-assisted conditions. These hybrid materials possess the ordered mesostructure with uniform pore size distributions, thick framework walls, thermal stability and specific functional groups; and they are carefully characterized by XRD, N2 adsorption, TGA, FT-IR, TEM and NMR spectroscopies. Moreover, horseradish peroxidase (HRP) is immobilized on these new PMO composites for the first time, and their enzyme activity in the oxidation of 1,3,5-trimethylbenzene (TMB) is elevated in the range of 25–59% compared with that of free HRP in solution. Again, the HRP immobilized samples can be reused for many cycles, resulting from the interfacial activation of the enzyme when it is attached to the surface of hybrid hosts where is filled with organic groups and hydrophobic parts.

Graphical abstractThe relative activity of immobilized HRP on new mesoporous organosilica is all dramatically improved.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► New mesoporous organosilicas with hydrophilic groups of –OH, –O– and –S– is synthesized. ► The resulting PMOs composites MGn have ordered 2D hexagonal mesoporous structure. ► HRP is immobilized in various MGn materials to catalyze oxidation of TMB. ► HRP/MGn catalysts have 25–59% higher activity than that of free HRP in solution. ► The HRP immobilized on PMO samples can be reusable.