Abstract: Provided are a valve unit and a microfluidic device including the valve unit. The valve unit includes: a valve substance container containing a valve substance, the valve substance including a phase change material that is solid at ambient temperature and melts by absorbing energy; a valve connection path connecting the valve substance container to a channel forming a fluid passage; and a pair of drain chambers formed along the channel at both sides of the valve connection path.

Abstract: A centrifugal force-based microfluidic device for nucleic acid extraction and a microfluidic system are provided. The microfluidic device includes a body of revolution; a microfluidic structure disposed in the body of revolution, the microfluidic structure including a plurality of chambers, channels connecting the chambers, and valves disposed in the channels to control fluid flow, the microfluidic structure transmitting the fluid using centrifugal force due to rotation of the body of revolution; and magnetic beads contained in one of the chambers which collect a target material from a biomaterial sample flowing into the chamber, wherein the microfluidic structure washes the magnetic beads which collect the target material, and separates nucleic acid by electromagnetic wave irradiation from an external energy source to the magnetic beads.

Abstract: Provided is a method for concentrating and disrupting cells or viruses, the method employs magnetic particles which are capable of binding the cells or viruses to capture the cells or viruses and a laser to disrupt the cells or viruses. Since the same particles are used in target cell separation and cell lysis, there is no need to add additional particles in a laser lysis process, and thus integration of a target cell separation, concentration, purification, and nucleic acid extraction process is easy.

Abstract: Provided herein are a method and an apparatus for isolating nucleic acids from cells. The method comprises introducing carbon nanotubes (CNTs) and silica beads into a solution containing the cells, irradiating the solution with a laser beam disrupt the cells releasing the nucleic acids from the disrupted cells, thereby binding the nucleic acids to the silica beads, and adding a nucleic acid eluting solution to the silica beads to which the nucleic acids are bound, to elute the nucleic acids from the silica beads.

Abstract: Provided are an apparatus and a method of controlling a microfluidic system, and the microfluidic system. The apparatus of controlling the microfluidic system includes a central control block controlling an operation of the microfluidic system, a rotator control block controlling a rotator, a position control block controlling the position of a moving unit, the moving unit moving to a position of the microfluidic structure, and a radiation energy source control block controlling energy of a radiation energy source, the radiation energy source using an electromagnetic wave to scan over a position of the microfluidic structure. Such a configuration allows effective control of a miniaturized portable microfluidic system.

Abstract: A centrifugal force based microfluidic device including a thermal activation unit, a microfluidic system including the same, and a method of operating the microfluidic system are provided. The thermal activation unit accompanies a temperature change in order to carry out its functions and having heat generation particles that absorb electromagnetic waves and generate heat in the activation unit therein.

Abstract: Provided is a method of mixing fluids including introducing at least two kinds of fluids to a chamber of a substrate including a microchannel structure; and alternately rotating the substrate clockwise and counter-clockwise until the at least two kinds of fluids are mixed, wherein the rotation is changed from one direction to the opposite direction before a vortex created in the mixing chamber by the one direction rotation disappears.

Abstract: A centrifugal force-based microfluidic device for the detection of a target biomolecule and a microfluidic system including the same are provided. The device includes a body of revolution; a microfluidic structure disposed in the body of revolution including chambers, channels connecting the chambers, and valves disposed in the channels to control fluid flow, the microfluidic structures transmitting fluid using centrifugal force due to rotation of the body of revolution; and beads disposed in the microfluidic structures, the beads having capture probes on the surfaces thereof which are selectively bonded with target protein; and a detection probe disposed in the microfluidic structures and selectively bonded to the target protein, and which includes a material required to express an optical signal, wherein the microfluidic structure mixes the beads, biological samples, and the detection probe to react and washes and separates the beads after the reaction.

Abstract: A valve unit, a reaction apparatus with the same, and a method of forming a valve by injecting a valve material into a channel are provided. The valve unit comprises a fluid channel constituting a flow path of a fluid and having a portion containing a first area of a first dimension (“D1”) and a second area of a second dimension (“D2”), wherein D1<D2, the second area is located on one side of the first area, and the first area has a distance of G in the direction of the fluid channel; and a valve formed in the first area of the fluid channel by filling the first area and made of a phase changeable valve material.

Abstract: A centrifugal micro fluidic system and a centrifugal magnetic position control device used in the centrifugal micro fluidic system for controlling the position of magnetic beads are provided. The centrifugal micro fluidic system comprising, a rotatable platform; a micro fluidic structure which is disposed in the platform; and a plurality of objects which include functional groups on surfaces thereof so as to capture a target material from the fluid and carry the target material while being suspended in and separated from the fluid in the micro fluidic structure, wherein the movements of the objects are controlled by a force affecting the objects differently compared to the force's effect on the fluid. When the objects are made of a magnetic material, the force may be a magnetic force applied by the centrifugal magnetic position control device.

Abstract: Provided are a valve unit and a reaction apparatus having the valve unit. The valve unit includes a phase transition material, which melts and expands upon an application of the electromagnetic waves to the valve filler, and the valve filler is directed into the channel through the connection passage and closes the channel. The valve unit also includes heat generation particles, which are dispersed in the phase transition material and generate heat upon an application of electromagnetic wave energy.

Abstract: Provided are a magnetic microparticle separation device for separating and purifying target biomolecules and a microfluidic system using the device. The device includes a magnetic microparticle, a chamber to receive a buffer, a channel including an inlet, outlet and a connecting portion which is connected to and fluid communicates with the chamber, wherein a fluid sample containing the target biomolecules and magnetic microparticle flows through the channel and the magnetic microparticle which captures the target biomolecules are separated from the fluid sample.

Abstract: Provided is a droplet dispensing device having a nonconductive capillary nozzle. The droplet dispensing device comprises: a nonconductive capillary nozzle disposed in a downward position; a pump connected with the nonconductive capillary nozzle through a hermetically sealed fluid tube and generating a negative pressure to decrease the influence of gravity on a solution within the nonconductive capillary nozzle and the fluid tube; and an open circuit voltage supplier applying a voltage to the solution. The droplet dispensing device supplies the solution by capillary force to regularly maintain the shape of a droplet surface in the tip of the nonconductive capillary nozzle without using a separate driving device.

Abstract: A cell lysis device for lysing cells or viruses, comprising a cell lysis tube having a sample inlet; a pump connected to the cell lysis tube for transferring a sample into the tube; a sealing unit for reversibly sealing a specific region of the tube; and a laser source for generating a laser is provide. Further, a method of lysing cells or viruses using the cell lysis device is provide. The method comprises introducing a sample containing cells or viruses and optionally magnetic beads to the cell lysis tube through the sample inlet; transferring the sample to a specific region in the cell lysis tube by means of the pump; temporarily sealing the region of the cell lysis tube where the sample is placed with the sealing unit; irradiating the sample with the laser; removing the sealing unit from the cell lysis tube; and discharging the sample from the cell lysis tube by means of the pump.

Abstract: An apparatus separating a polarizable analyte using dielectrophoresis includes a vessel including a membrane having a plurality of nano- to micro-sized pores, the membrane disposed inside the vessel, electrodes generating spatially non-uniform electric fields in the nano- to micro-sized pores of the membrane when an AC voltage is applied to the electrodes, and a power source applying the AC voltage to the electrodes, wherein a sectional area of the pores varies along a depth of the pores. A method of separating a polarizable material uses the apparatus.

Abstract: Provided herein is a method and apparatus for disrupting cells and purifying nucleic acids in a single chip. The method comprises irradiating a chip with a laser beam, wherein the chip comprises a solid support on which a cell lysis enhancing metal oxide layer, and a cell binding metal oxide layer have been deposited.

Abstract: A valve unit and an apparatus having the same include a plug which includes a phase change material in a solid state at a room temperature and a plurality of fine heat-dissipating particles dispersed in the phase change material. The fine heat-dissipating particles dispersed in the phase change material dissipate heat by absorbing an electromagnetic wave energy generated by electromagnetic wave radiation from the outside and block fluid flow in a path formed by a channel. As an external energy source irradiates an electromagnetic wave on the plug, the plurality of fine heat-dissipating particles dissipate heat and the phase change material becomes molten, thus opening the path to allow the fluid to flow.

Abstract: Provided is a device for controlling a particle distribution in a droplet including particles. The device includes: a first electrode for developing an electric field in the vicinity of the droplet; and a second electrode for developing the electric field that is fixed to a substrate, is insulated from the first electrode, and located at about the center of the droplet. A micro electrode system including a circular electrode placed along a droplet rim and a point electrode at about the center of the bottom is used to cause radial electroosmotic flow, thereby obtaining a uniform solute distribution after complete evaporation of the droplet. The direction and strength of the radial electroosmotic flow can be varied and the radial electroosmotic flow is periodically applied. Particles used to obtain uniformity are selected from the group consisting of a polymer, an organic substance, an inorganic substance, a metal, and a biomolecule. The particles can be neutral, negatively charged or positively charged.

Abstract: Provided is a quantitative cell dispensing apparatus using liquid droplet manipulation, for quantitatively dispensing cells from hydrophilic suspension containing a plurality of cells. The quantitative cell dispensing apparatus includes hydrophilic suspension, a liquid droplet manipulation unit, a dispensing unit, a sensing unit, and a control unit. The hydrophilic suspension includes a plurality of cells and electrolyte, and the liquid droplet manipulation unit. The liquid droplet manipulation unit includes an inlet and a liquid droplet outlet portion. The dispensing unit discharges a liquid droplet received from the liquid droplet outlet portion to a target portion. The sensing unit optically senses liquid droplets distributed on a panel of the liquid droplet manipulation unit.

Abstract: A microfluidic device for the concentration and lysis of cells or viruses and a method of concentrating and lysing cells or viruses using the microfluidic device include: magnetic beads, a reaction chamber in which the magnetic beads are accommodated and a laser source. The reaction chamber includes a plurality of electrodes which cross each other and are separated by a dielectric to generate an electric field and a vibrating part agitating the magnetic beads in the chamber. The laser source radiates a laser onto the magnetic beads in the reaction chamber.