No abstract

Cell arraying with single cell per trap is demonstrated using image dielectrophoresis(DEP) and leads to a 5 by 5 single cells array. The tunable energy wells, which were induced by established patterns and image control, were used to confine NIH/3T3 cells. Image was used to help cells overcome the energy barriers. It allows the controllability to rearrange cells, including locally dislodging the excess cells and repositioning them in non-occupant traps. The viability of post-assembled cells that were identified by fluorescence staining of FDA is about 90%. The continuous temperature monitoring shows that the device used reached its thermal equilibrium of 36 , close to the 3T3 culture temperature of 37 .

The Inside Cover Picture shows three‐dimensionally extended host electrodes, which drastically enhance the sensitivities of non‐enzymatic hydrogen peroxide sensing by two orders of magnitude. These nanorods not only offer a greatly enlarged sensing area and fast charge‐transport channels, but they also significantly enhance the hydrophilicity of the electrode. More details can be found in the Full Paper by S.‐Y. Lu and co‐workers on page 552 in Issue 4, 2016 (DOI: 10.1002/celc.201500524).

A new concept of three‐dimensionally extended host electrodes is proposed with the fabrication and applications of fluorine‐doped tin oxide (FTO) nanorod array based host electrodes as an example. The FTO nanorod arrays were grown on top of commercial FTO glass through a vapor–liquid–solid process by using Au nanocrystals as the anisotropic growth catalyst, tin powders as the precursor, and NH4F as the fluorine source. This three‐dimensionally extended FTO nanostructure was then decorated with Pt nanocrystals, using a polyol method, to serve as a non‐enzymatic sensing electrode for H2O2. These FTO nanorods not only offer greatly enlarged sensing areas and fast charge transport channels, but also significantly enhance the hydrophilicity of the electrode, all of which are beneficial for the electrochemical sensing of aqueous samples. A two order of magnitude improvement in sensitivity toward H2O2 over the plain commercial FTO glass was achieved, reaching a high sensitivity value of 543 mA M−1 cm2.