Reversible HRP immobilization onto porous SiO2surface using DDI and the corresponding enzymatic activity.(a) A schematic illustration of reversible enzyme immobilization onto PSiO2 surface using DDI approach. Note: These schematics are for illustration purposes only as all modifications occur also inside the pores. (b) Relative activity of HRP immobilized via DDI onto PSiO2. (c) Removal of the DNA-enzyme conjugates form the surface by mild dehybridization. Two consecutive cycles of DNA-enzyme hybridization/dehybridization are performed. (d) HRP enzymatic activity is quantified using the Ampliflu Red assay in which oxidation of the non-fluorescence Ampliflu substrate occurs in the presence of HRP and H2O2 to fluorescence resorufin.
Shtenberg et al. Nanoscale Research Letters 2012 7:443 doi:10.1186/1556-276X-7-443