@misc{PacholskiAgarwalBalderasValadez2016, author = {Pacholski, Claudia and Agarwal, Vivechana and Balderas-Valadez, Ruth Fabiola}, title = {Fabrication of porous silicon-based optical sensors using metal-assisted chemical etching}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-394426}, pages = {21430 -- 21434}, year = {2016}, abstract = {Optical biosensors based on porous silicon were fabricated by metal assisted chemical etching. Thereby double layered porous silicon structures were obtained consisting of porous pillars with large pores on top of a porous silicon layer with smaller pores. These structures showed a similar sensing performance in comparison to electrochemically produced porous silicon interferometric sensors.}, language = {en} } @misc{OlejkoCywińskiBald2016, author = {Olejko, Lydia and Cywiński, P. J. and Bald, Ilko}, title = {An ion-controlled four-color fluorescent telomeric switch on DNA origami structures}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-95831}, pages = {10339 -- 10347}, year = {2016}, abstract = {The folding of single-stranded telomeric DNA into guanine (G) quadruplexes is a conformational change that plays a major role in sensing and drug targeting. The telomeric DNA can be placed on DNA origami nanostructures to make the folding process extremely selective for K+ ions even in the presence of high Na+ concentrations. Here, we demonstrate that the K+-selective G-quadruplex formation is reversible when using a cryptand to remove K+ from the G-quadruplex. We present a full characterization of the reversible switching between single-stranded telomeric DNA and G-quadruplex structures using F{\"o}rster resonance energy transfer (FRET) between the dyes fluorescein (FAM) and cyanine3 (Cy3). When attached to the DNA origami platform, the G-quadruplex switch can be incorporated into more complex photonic networks, which is demonstrated for a three-color and a four-color FRET cascade from FAM over Cy3 and Cy5 to IRDye700 with G-quadruplex-Cy3 acting as a switchable transmitter.}, language = {en} }