Conjugation of enzymes to a porous SiO
surface using DDI approach. (a) A schematic representation of the synthetic steps required for enzyme immobilization onto PSiO2 through DDI approach. The porous scaffold is first modified with GPTS to graft the amine-modified capture strand (aD1) that serves as an anchor for the following hybridization process. (b) Results of fluorescence labeling experiments to confirm the specificity of the DDI method. Complete bioconjugation; aD1 is attached to the silane-modified porous surface followed by hybridization of the complementary strand labeled with TAMRA fluorophore. (c) Control experiment; no GPTS is used (silanization step).