Controlled release of chol-TEG-DNA from Nano- and micropatterned SU-8 surfaces by a spreading lipid film.
Erkan Y., Halma K., Czolkos I., Jesorka A., Dommersnes P., Kumar R., Brown T., Orwar O.
We report the controlled release of immobilized cholesteryl-tetraethyleneglycol-DNA (chol-DNA) from micropatterned SU-8 surfaces by a spreading lipid film. The release of chol-DNA is rapid and on the order of the spreading rate of the lipid film beta = 1-3 microm2/s ( approximately 10(5) molecules of DNA per second). The lipid film serves as a poor solvent for the DNA adduct, which upon contact redistributes into the aqueous phase. Thus, the release of DNA is accompanied by a change in surface hydrophobicity. The method can be used for creating arbitrary concentration profiles of DNA in solution over time or to dynamically change surface properties on demand in, for example, micro- and nanofluidic devices. Examples of DNA release from spiral, comb, meander, and triangular as well as from nanoscale SU-8 lanes are shown.