Abstract:
The invention relates to a capillary electrophoresis apparatus, comprising background solution containing reservoirs, which are interconnected by way of a separating capillary (1), current electrodes (E) connected to a voltage source, and a detector (4) essentially in the proximity of the outlet end of the separating capillary (1), as well as one or more solution reservoirs (R1-R3) on the injection side of the apparatus and one or more solution reservoirs (R4-R6) on the detector side of the apparatus, the ends of the separating capillary (1) being placed in expansions (5, 7), intended for feeding various solutions from the reservoirs (R1-R6) and extending from the bottom ends of capillary tubes (2, 3), said expansions extending as waste ducts (W1, W2) to waste containers, said waste containers being located at a distance from the ends of the separating capillary (1), and the current electrodes (E) being located in the waste ducts (W1, W2), preferably in the proximity of the discharge ends thereof.
Abstract:
Apparatus for conducting electrophoresis separation therein. The apparatus includes a chamber having therein a body of separating gel for carrying therein an electrophoresis separation and electrodes for connecting the chamber to an external electrical power source, thereby driving the electrophoresis separation. According to the invention at least one of the electrodes also providing ions for driving the electrophoresis separation. In one preferred embodiment, the apparatus is a cassette substantially closed before, during and after electrophoresis separation. According to an aspect of the invention the pH in the body of separating gel is substantially constant during the electrophoresis separation.
Abstract:
Process for the selective separation of electrically charged target molecules in an analytical mixture by means of capillary affinity gel electrophoresis, using a capillary tube which is at least partly filled with a polymer gel, whereby receptors for target molecules are covalently bound to the polymer, and an electric field of at least 50 volts/cm is applied, characterized in that (a) the capillary tube is charged with the analytical mixture, (b) in a first separation stage the target molecules in the analytical mixture are bound to the receptors and the remaining components are eluted, optionally while splitting open, and (c) in a second stage of the process the elution conditions are changed, optionally in stages, so that the affinity of the target molecules for the receptor is eliminated and the target molecules are eluted and detected, optionally whilst splitting open.
Abstract:
A method of producing a silver halide photographic emulsion in which a silver ion concentration in precipitation of a silver halide emulsion in a precipitation bath is controlled, wherein a precipitation bath in which stirring is conducted rapidly and uniformly, and crystal formation and crystal growth are uniformly performed is used, the method comprises the steps of: in a start period of precipitation, quantitavely adding a silver nitrate solution and a halogen salt solution at a constant ratio flow rate; when an EAg value reaches a designated EAg value region in the vicinity of a preset target EAg value, starting a control of an adding rate of the halogen salt solution by using a controller which has an operation period equal to or shorter than 1 sec.; and after holding a tuning parameter of a proportional, integral and differential (PID) action controller to a minimum response level, conducting a control in which the tuning parameter is switched to an optimum control tuning parameter which corresponds to the preset target value and a solute rate of silver/halogen ions to be added.
Abstract:
An automated electrophoretic system is disclosed. The system employs a capillary cartridge having a plurality of capillary tubes. The cartridge has a first array of capillary ends projecting from one side of a plate. The first array of capillary ends are spaced apart in substantially the same manner as the wells of a microtitre tray of standard size. This allows one to simultaneously perform capillary electrophoresis on samples present in each of the wells of the tray. The system includes a stacked, dual carrousel arrangement to eliminate cross-contamination resulting from reuse of the same buffer tray on consecutive executions from electrophoresis. The system also has a gel delivery module containing a gel syringe/a stepper motor or a high pressure chamber with a pump to quickly and uniformly deliver gel through the capillary tubes. The system further includes a multi-wavelength beam generator to generate a laser beam which produces a beam with a wide range of wavelengths. An off-line capillary reconditioner thoroughly cleans a capillary cartridge to enable simultaneous execution of electrophoresis with another capillary cartridge. The streamlined nature of the off-line capillary reconditioner offers the advantage of increased system throughput with a minimal increase in system cost.
Abstract:
An automated capillary zone electrophoretic system is disclosed. The system employs a capillary cartridge having a plurality of capillary tubes. The cartridge has a first array of capillary ends projecting from one side of a plate. The first array of capillary ends are spaced apart in substantially the same manner as the wells of a microtitre tray of standard size. This allows one to simultaneously perform capillary electrophoresis on samples present in each of the wells of the tray. The system includes a stacked, dual carrousel arrangement to eliminate cross-contamination resulting from reuse of the same buffer tray on consecutive executions from electrophoresis. The system also has a container connected to the detection end of the capillaries. The container is provided with valving which facilitate cleaning the capillaries, loading buffer into the capillaries, introducing samples to be electrophoresced into the capillaries, and performing capillary zone electrophoresis on the thus introduced samples.
Abstract:
An array of electrodes at the atomic or nano scale (nanoelectrodes) is built on a chip. The spatial distribution, height, width and electrochemical composition of the nanoelectrodes is varied, such that protein-specific electronic receptors are built directly on the chip with the nanoelectrodes without the use of any specific binding agents or molecules. Because of their size, a very large number of different receptors can be built as arrays on a single chip. The chip can be used to detect, characterize and quantify single molecules in solution such as individual proteins, complex protein mixtures, DNA or other molecules.
Abstract:
Microfluidic devices are fabricated by fabricating structures that are used to align elements that are to be attached to the devices or tools that are to be used in further fabrication steps on those devices. Elements to be attached include additional substrate layers, external sampling elements, e.g. capillaries, and the like. Preferred alignment structures include wells over which reservoirs are positioned, notches for use with alignment keys to align substrate layers or for receiving additional structural elements, and targets or guide holes for receiving tooling in further fabrication steps.
Abstract:
The use of a gel produced by polymerization of a dextran derivative which exhibits groups that contain an alkene structure, for separating nucleic acid by electrophoresis.
Abstract:
Devices and methods are disclosed for moving charged molecules through a medium by the application of a plurality of electrical fields of sufficient strength and applied for sufficient amounts of time so as to move the charged molecules through the medium. The devices although preferably small in size, preferably generate large numbers (100 or more) of electrical fields to a movement area which preferably contains a liquid buffered or gel medium. Mixtures of charged molecules are pulled through the gel by the force of the electrical fields. The fields are preferably activated simultaneously or sequentially one after another at various speeds to create complex force field distributions or moving field waves along the separation medium. Charged molecules capable of moving quickly through the gel will be moved along by the faster moving field waves and be separated from slower moving molecules. The fields can be activated by computer software and can be used to move molecules away from and toward each other to obtain rapid and complex chemical synthesis, sequencing or reaction protocols.