Experimental results are presented regarding the influence of bubble formation on the capillary filling speed of water in $\mathrm{Si}{\mathrm{O}}_2$ nanoslits with heights ranging from $33\text{to}158\mathrm{nm}$ . The formation of an isolated pinned bubble in a nanoslit with a height of $111\mathrm{nm}$ causes an immediate decrease in the filling speed. In nanoslits with heights below $100\mathrm{nm}$ , pinned bubbles are continuously formed at the advancing liquid meniscus. This observed increase in bubble density, which increases the fluidic resistance, quantitatively coincides with an observed reduction of the filling speed during filling of nanoslits with heights below $100\mathrm{nm}$ .

We present results regarding the fast and inexpensive fabrication of polymer biochips for investigating the statics and dynamics of DNA confined in nanochannels. The biochips have been fabricated by means of nanoimprint lithography (NIL) in low molecular weight polymethyl methacrylate (PMMA) using a 4 inch diameter two-level hybrid stamp. The fluidic structures were sealed using thermal polymer fusion bonding. The stamp has nanometer- and micrometer-sized protrusions defined in a thermally grown SiO(2) layer and the sol-gel process derived duromeric hybrid polymer Ormocomp, respectively. The stamp is compatible with molecular vapor deposition (MVD), used for applying a durable chlorosilane based antistiction coating, and allows for imprint up to a temperature of 270 °C. The extension of YOYO-1 stained T4 GT7 bacteriophage DNA inside the PMMA nanochannels has been experimentally investigated using epi-fluorescence microscopy. The measured average extension length amounts to 20% of the full contour length with a standard deviation of 4%. These results are in good agreement with results obtained by stretching DNA in conventional fused silica nanochannels.