The invention relates to a method for depositing nano-objects on the surface of a gel comprising the steps of: a) providing a gel having a polymer matrix and a solvent within the polymer matrix, the polymer matrix forming a three-dimensional network which is capable of swelling in the presence of the solvent, wherein the solubility of the polymer matrix in the solvent at 1 bar and 25? C. is less than 1 g/l, wherein the gel has a rigidity gradient on the micrometer scale of less than 10%, then b) depositing nano-objects on the surface of the gel, the nano-objects having a mean diameter greater than or equal to the mean diameter of the pores of the gel, then c) evaporating the solvent from the gel at least until the content of solvent no longer varies over time, under the proviso that, at the start of evaporation, the content of mineral salts in the solvent is less than 6 g/l, the gel capable of being obtained and the uses thereof.

A microfluidic product utilizing gradient surface energy coatings for fluid control comprising a plurality of fluid passages wherein at least one fluid passage comprises a coating configured to control liquid flow wherein the coating configured to control liquid flow comprises a gradient surface energy coating from a proximal location to a distal location on a surface of the fluid passage. The product can include uniform regions and surface gradient regions in the same passage. Coating compositions and product dimensions can be selected to provide control over different flow properties including fluid velocity, reduction and acceleration of fluid flow, and starting and stopping fluid flow.

Provided are systems and methods for the post-treatment of dry adhesive microstructures. The microstructures may be post-treated to comprise mushroom-like flaps at their tips to interface with the contact surface. In some aspects, a change in material composition of the microstructures in a dry adhesive may affect mechanical properties to enhance or diminish overall adhesive performance. For example, conductive additives can be added to the material to improve adhesive performance. In other aspects, microstructures comprising conductive material may allow for pre-load engagement sensing systems to be integrated into the microstructures.

A microfluidic product utilizing gradient surface energy coatings for fluid control comprising a plurality of fluid passages wherein at least one fluid passage comprises a coating configured to control liquid flow wherein the coating configured to control liquid flow comprises a gradient surface energy coating from a proximal location to a distal location on a surface of the fluid passage. The product can include uniform regions and surface gradient regions in the same passage. Coating compositions and product dimensions can be selected to provide control over different flow properties including fluid velocity, reduction and acceleration of fluid flow, and starting and stopping fluid flow.

A method is provided for fabricating a construction (10) having a functional side (12). The method includes the steps of: supplying a flexible substrate (20); attaching one or more structures (30) to the substrate (20) on a surface or side thereof facing the functional side (12) of the construction (10); and forming one or more features, for example, such as fibrils (39), on at least one of the structures (30), wherein the features have at least one dimension which is at least one of micro-sized or nano-sized.

According to one embodiment, a method for creating a metal nanowire mesh the method includes forming a first layer of block copolymer, causing the block copolymer to become aligned in approximately straight lines, infiltrating one phase of the block copolymer with a metal, and removing the block copolymer where the metal remains after the block copolymer is removed. Furthermore, the method includes forming a second layer of block copolymer, causing the block copolymer in the second layer to become ordered in approximately straight lines oriented at an angle from greater than 0 degrees to 90 degrees from a mean direction of longitudinal axes of the remaining metal, infiltrating one phase of the block copolymer in the second layer with a second metal, and removing the block copolymer in the second layer where the second metal remains above the metal after the block copolymer in the second layer is removed.

Provided herein is a hierarchical superhydrophobic surface comprising an array of first geometrical features disposed on a substrate comprising a first material, and an array of second geometrical features disposed on the first features to form a hierarchical structure and a terminal level disposed on the second features, wherein the terminal level comprises a second material, the second material being different from the first material. The second material has a hydrophilicity different from the hydrophilicity of at least one of 1) the hydrophilicity of the second material and 2) hydrophilicity induced by the hierarchical structure. The present disclosure further methods of preparing hierarchical superhydrophobic surfaces and medical devices comprising the hierarchical superhydrophobic surfaces.

The disclosed invention provides a biofluid collection device configured with a hexagonal open microfluidic network, which facilitates nanoliter-scale biofluid collection and transport for biosensing applications. In one embodiment, a biofluid sensing device placed on the skin for measuring a characteristic of an analyte in sweat includes one or more biofluid sensors and a hexagonal open microfluidic network biofluid collector. The disclosed collector provides a volume-reduced pathway for sweat biofluid between the one or more sensors and sweat glands when the device is positioned on the skin. In another embodiment, a biofluid collector includes a network of microchannels comprising three or more repeatedly intersecting channels that provide redundant pathways for biofluid transport.

An article with controllable wettability includes a substrate and a layer of a composite material supported on the substrate. The layer has an exposed surface and the composite material includes particles that have controllable polarization embedded fully or partially in a matrix. A controller is operable to selectively apply a controlled variable activation energy to the layer. The controllable polarization of the particles varies responsive to the controlled variable activation energy such that a wettability of the exposed surface also varies responsive to the controlled variable activation energy.

A microelectromechanical systems (MEMS) structure includes a substrate, an epitaxial polysilicon cap located above the substrate, a first cavity portion defined between the substrate and the epitaxial polysilicon cap, and a first graphene component having at least one graphene surface immediately adjacent to the first cavity portion.