Aldehyde-terminated amorphous carbon substrates for the fabrication of biomolecule arrays

Amorphous carbon thin films are easily deposited at room temperature, readily functionalized with alkene-containing molecules through a UV photochemical reaction, and provide a robust surface capable of supporting chemical and biomolecule array fabrication. Aldehyde-terminated amorphous carbon substrates were fabricated via the attachment of a 2-(10-undecen-1-yl)-1,3-dioxolane molecule. The surfaces were then deprotected in 1.5 M HCl to yield an aldehyde-terminated surface that is readily reactive with amine containing molecules. An array of amine-modified oligonucleotides was prepared on aldehyde-terminated surfaces prepared on both amorphous carbon and on gold self-assembled monolayers, and the fluorescence background, feature signal-to-noise ratio, and hybridization densities were compared. The aldehyde-terminated amorphous carbon substrates offer inherently lower background fluorescence intensity and a greater number of hybridization-accessible sites.