Abstract: Microchannels in hydrogels play an essential role in enabling a smart contact lens. A wearable contact lens is disclosed herein that uses microchannels and connected chambers located in poly-2-hydroxyethyl methacrylate (poly(HEMA)) hydrogel that is used in a commercial contact lens with three-dimensional (3D) printed mold. The corresponding capillary flow behaviors in these microchannels were investigated. Different capillary flow regimes were observed in these microchannels, depending on the hydration level of the hydrogel material. In particular, it was found that a peristaltic pressure could reinstate flow in a dehydrated microchannel, indicating the motion of eye-blinking may help tear flow in a microchannel-containing contact lens. Colorimetric pH and electrochemical Na+ sensing capabilities were demonstrated in these microchannels. Micro-engineered contact lenses formed using poly(HEMA) hydrogel can be used for various biomedical applications such as eye-care and wearable biosensing.

Abstract: An assembly of nanoelements forms a three-dimensional nanoscale circuit interconnect for use in microelectronic devices. A process for producing the circuit interconnect includes using dielectrophoresis by applying an electrical field across a gap between vertically displaced non-coplanar microelectrodes in the presence of a liquid suspension of nanoelements such as nanoparticles or single-walled carbon nanotubes to form a nanoelement bridge connecting the microelectrodes. The assembly process can be carried out at room temperature, is compatible with conventional semiconductor fabrication, and has a high yield. The current-voltage curves obtained from the nanoelement bridge demonstrate that the assembly is functional with a resistance of ?40 ohms for gold nanoparticles. The method is suitable for making high density three-dimensional circuit interconnects, vertically integrated nanosensors, and for in-line testing of manufactured conductive nanoelements.

Abstract: An assembly of nanoelements forms a three-dimensional nanoscale circuit interconnect for use in microelectronic devices. A process for producing the circuit interconnect includes using dielectrophoresis by applying an electrical field across a gap between vertically displaced non-coplanar microelectrodes in the presence of a liquid suspension of nanoelements such as nanoparticles or single-walled carbon nanotubes to form a nanoelement bridge connecting the microelectrodes. The assembly process can be carried out at room temperature, is compatible with conventional semiconductor fabrication, and has a high yield. The current-voltage curves obtained from the nanoelement bridge demonstrate that the assembly is functional with a resistance of ?40 ohms for gold nanoparticles. The method is suitable for making high density three-dimensional circuit interconnects, vertically integrated nanosensors, and for in-line testing of manufactured conductive nanoelements.