Abstract:
In one embodiment of the present invention, an apparatus for one-step flow control at a micro-channel crossing comprises a first micro-channel and a second micro-channel, a plurality of magnetic valves, and a guiding magnet. The guiding magnet produces a proximal magnetic field gradient at a location of each of the plurality of magnetic valves when an operator places the guiding magnet in a vicinity of the chip. The vicinity of the chip comprises a plurality of guiding magnet position ranges. The operator repositions guiding magnet in order to actuate the plurality of magnetic valves simultaneously. Depending on the position of the guiding magnet, the passages are blocked or unblocked to stop or let the fluid flow in a given crossing.
Abstract:
In one embodiment as described in this section, an apparatus for mixing of microfluidic streams on a chip is presented, which comprises a micro-channel and a plurality of magnetic valves on the chip. A guiding magnet produces a proximal magnetic field gradient to exert a force on a bead in a cavity when placed at in a vicinity of the chip. The bead-cavity combination form a magnetic valve. In one embodiment, the mouth of the cavity is tapered so to prevent the magnetic bead from completely blocking the corresponding micro-channel section to enhance the mixing of microfluidic streams at the narrowed fluid path. In one embodiment, magnetically actuated valves direct the flow in a microfluidic system in one of several flow paths wherein the mixing characteristics of the paths are different.
Abstract:
An apparatus, system and method for determining the osmolarity of a fluid. The system includes an apparatus having: a chip with a substantially planar top surface; a first circuit portion and a second circuit portion, each having a plurality of redundant electrically conductive lines disposed on the top surface; and a gap disposed between the first circuit portion and the second circuit portion, wherein a circuit is created when a fluid sample bridges the gap and connects the first circuit portion and the second circuit portion.
Abstract:
A device for flowing a liquid on a surface comprises: a flow path. A first port supplies the liquid to one end of the flow path and applies a first port pressure for retaining the liquid when the flow path is remote from the surface. A second port receives the liquid from the other end of the flow path and applies a second port pressure such that the difference between the first and second negative port pressures is oriented to promote flow of the liquid from the first port to the second port via the flow path in response to the flow path being located proximal to the surface and the liquid in the device contacting the surface. The first and second port pressures are such that the liquid is drawn towards at least the second port in response to withdrawal of the flow path from the surface. Such devices may employ microfluidic technology and find application in surface patterning.
Abstract:
A method for producing a monolayer of molecules on a surface comprises: loading a stamp with seed molecules; transferring seed molecules from the stamp to the surface; and, amplifying the seed molecules via an amplifying reaction to produce the monolayer. The method permit generation of complete monolayers from incomplete or sparse monolayers initially printed on the surface.
Abstract:
A device for flowing a liquid on a surface comprises: a flow path. A first port supplies the liquid to one end of the flow path and applies a first port pressure for retaining the liquid when the flow path is remote from the surface. A second port receives the liquid from the other end of the flow path and applies a second port pressure such that the difference between the first and second negative port pressures is oriented to promote flow of the liquid from the first port to the second port via the flow path in response to the flow path being located proximal to the surface and the liquid in the device contacting the surface. The first and second port pressures are such that the liquid is drawn towards at least the second port in response to withdrawal of the flow path from the surface. Such devices may employ microfluidic technology and find application in surface patterning.
Abstract:
A method for fabricating silicone elastomer stamps with hydrophilic surfaces is provided. The concept of polymer grafting is used to produce the stamps. The stamps thus produced have the great advantage that grafting of a thin hydrophilic polymer on a hydrophobic PDMS surface can render PDMS stamps permanently hydrophilic. With such stamps it becomes possible to print aqueous or highly polar inks reproducibly over days and weeks.
Abstract:
A patterning device comprises a patterning cavity which has an opening located at the surface of the patterning device within a transfer region, where a substrate during patterning comes into conformal contact with the patterning device. A service cavity is located in a service region of the patterning device and is connected to the patterning cavity, such that a patterning fluid is able to flow from the service cavity to the patterning cavity. A patterning method uses this device.
Abstract:
Disclosed herein is a microfluidic device comprising a chip; a flow channel being disposed in the chip; the flow channel being in communication with an entry port and an exit port; the flow channel being operative to permit the flow of a library from the entry port to the exit port; a substrate; the substrate being disposed upon the chip; the substrate being operative to act as an upper wall for the flow channels; and a plurality of receptors; the plurality of receptors being disposed on the substrate; the plurality of receptors being operative to interact with an element from the library.
Abstract:
A stamp for transferring a pattern to a substrate in the presence of a third medium, includes a permeable hydrophilic matrix for guiding excess third medium away from the surface of the stamp.