Non-destructive verification of PNA immobilization using click chemistry

Abstract

This study is designed for developing a fluorescent immobilization method using click chemistry allowing a direct and non-destructive verification of immobilization for PNA microarray. We used a chemical reaction synthesizing a fluorescent triazole compound through copper (I)-catalyzed 1,3-dipolar cycloaddition from non-fluorescent molecules. We firstly verified fluorescence of synthesized triazole molecule from combining azidocoumarin and phenyl-acetylene in solution state by UV-visible and photoluminescence spectroscopy. Spectroscopic results exhibited that the product has excitation and emission peak around at 360nm and 430 nm respectively. Identifying fluorescent feature of triazole compound, azidocoumarin-linked PNA was spotted on the phenyl acetylene modified glass and reacted in click condition. The fluorescence from immobilization and hybridization are separately confirmed by array scanner since the wavelength of the immobilized region is different from that of target-labeled fluorescence. This fluorescent immobilization can serve a cost-reducing quality control method for PNA microarray.