We present a simple and cheap method for fabrication of silica nanofluidic devices for single-molecule studies. By imprinting sol-gel materials with a multi-level stamp comprising micro- and nanofeatures, channels of different depth are produced in a single process step. Calcination of the imprinted hybrid sol-gel material produces purely inorganic silica, which has very low autofluorescence and can be fusion bonded to a glass lid. Compared to top-down processing of fused silica or silicon substrates, imprint of sol-gel silica enables fabrication of high-quality nanofluidic devices without expensive high-vacuum lithography and etching techniques. The applicability of the fabricated device for single-molecule studies is demonstrated by measuring the extension of DNA molecules of different lengths confined in the nanochannels.
Mikkelsen, M. B. L., Letailleur, A. A., Søndergård, E., Barthel, E., Teisseire, J., Marie, R., & Kristensen, A. (2011). All-silica nanofluidic devices for DNA-analysis fabricated by imprint of sol-gel silica with silicon stamp. Lab on a Chip, 12(2), 262-267. https://doi.org/10.1039/c1lc20689c