Figure 16.

Click chemistry-mediated immobilization of nucleic acid probes on an electrophotonic ring resonator. (a) Two different diazonium salts (azidoaniline and 4-ethynylbenzene) are electrografted on the electrophotonic rings, which are electrically isolated. The individual microrings are then functionalized with alkyne- and azide-modified DNA probes using copper-catalyzed azide-alkyne click reaction. (b) First, the azide-modified sensor is functionalized with the alkyne-modified single-stranded DNA probe (ssDNA_alkyne). (c) Next, the alkyne-modified sensor is functionalized with the azide-modified single-stranded DNA probe (ssDNA_azide). The target sequences complementary to ssDNA_azide (d) ssDNA_alkyne (e) (labeled cDNA_azide and cDNA_alkyne, respectively) are introduced and hybridize to the functionalized sensors. Adapted from Ref. [59] in accordance with the Creative Commons Attribution 4.0 International (CC BY 4.0) license.