Utilizing Paper Or Thin Layer Plate Patents (Class 210/658)
  • Patent number: 4741830
    Abstract: New separation materials for thin layer chromatography are based on carrier materials coated with an adsorbent silica gel layer which has been surface-modified by a silanizing agent after the coating step. The degree of covering of the modifying reagent can be adjusted in a defined and controllable manner, e.g., from 0.15 to 0.8 .mu.mol/m.sup.2 in the case of reversed phase materials and 1.2 to 2.5 .mu.mil/m.sup.2 in the case of hydrophilic materials. A process for the preparation of these separation materials is also provided.
    Type: Grant
    Filed: February 11, 1987
    Date of Patent: May 3, 1988
    Assignee: Merck Patent Gesellschaft mit beschrankter Haftung
    Inventors: Heinz E. Hauck, Willi Jost
  • Patent number: 4737384
    Abstract: A process of depositing thin film onto a substrate using super-critical fluids.
    Type: Grant
    Filed: November 1, 1985
    Date of Patent: April 12, 1988
    Assignee: Allied Corporation
    Inventors: Andiappan K. S. Murthy, Alex Y. Bekker, Kundanbhai M. Patel
  • Patent number: 4726904
    Abstract: An apparatus for the separation of macroion groups from a mixture utilizing a three field device for generating forces on the macroions including means for applying a centrifugal force, means for applying a magnetophoretic force, and means for applying a constant or variable electrophoretic force. In a separation step the centrifugal and magetophoretic forces assist in forming the macroions in separate groups of concentric bands on a rotating platform. The constant electrophoretic force may be optionally used to assist in this step. In an analytical step to characterize the mass and charge of the macroions, the electrophoretic and magnetophoretic forces are used to oppose the centrifugal force to control and hold the macroion bands at fixed positions on the platform. A band detection means is used to characterize the positions of the macroion bands on the platform. The variable electrophoretic force may be optionally used in a detection part of the analytical step.
    Type: Grant
    Filed: December 17, 1984
    Date of Patent: February 23, 1988
    Assignee: Senetek P L C
    Inventor: William M. Ayers
  • Patent number: 4714555
    Abstract: A nitrate or a nitrate group-containing derivative of polysaccharide is useful as a separating agent for a chemical substance, especially an optical isomer.
    Type: Grant
    Filed: March 11, 1987
    Date of Patent: December 22, 1987
    Assignee: Daicel Chemical Industries, Ltd.
    Inventors: Tohru Shibata, Ichiro Okamoto
  • Patent number: 4711765
    Abstract: A sorption/desorption gas analysis apparatus includes a sorption/desorption bed having a thin layer of sorption material fixed to an outside surface of a first and a second adjacent tapered bed element arranged in a mutually mating configuration. The bed elements are further arranged to be selectively moved with respect to each other to produce a first flow volume therebetween past the sorptive material during a sorption mode of operation and a second substantially smaller flow volume past the sorptive material during a desorption mode of operation. The sorption/desorption bed is used in the gas analysis apparatus by first exposing the sorption bed to an impinging flow of a sample gas containing the constituent of interest which is sorbed by the sorptive material in the sorption mode of operation.
    Type: Grant
    Filed: July 2, 1986
    Date of Patent: December 8, 1987
    Assignee: Honeywell Inc.
    Inventors: Marion H. Cates, Eugene L. Szonntagh
  • Patent number: 4708782
    Abstract: A chromatography column-electrophoresis system for directing the fluid output from the column directly to a point of use, further resolution or separation, detection and/or identification while conditioning or preparing the output for analysis by another instrument such as a mass spectrometer. The system provides for substantially simultaneous analysis in a mass spectrometer, for example, material separated initially by the column, followed by electrophoretic separation and resolution. The chromatography column utilizes horizontal or radial flow of the sample fluid through the separating medium. The column may be of a type having a quickly replaceable or disposable separating medium, or the entire column may be of a readily replaceable or disposable type. The electrophoresis apparatus is of a capillary tube type, one embodiment of which utilizes a pair of capillary tubes thereby providing for continuous operation.
    Type: Grant
    Filed: September 15, 1986
    Date of Patent: November 24, 1987
    Assignee: Sepragen Corporation
    Inventors: Brian D. Andresen, Vinit Saxena
  • Patent number: 4678570
    Abstract: A planar centrifugal chromatography device includes a chamber (2), and a rotor (3) arranged therein, driven by a motor (12) and serving as a separating element. The rotor has a supporting plate (15) with an adsorbing medium (4) provided thereon. A collecting device (5) is arranged near the outer edge of the rotor, but within the chamber.The characteristics of the invention include the collecting device (5) and the rotor (3) being mounted on a common shaft (10) and each individual point of a wall of the collecting device (5) being farther away from the axis of rotation (14) than the point of the adsorbing medium (4) which is farthest from the axis of rotation (14), and include the distances of individual points on the wall of the collecting device (5), measured from the axis of rotation (14), varying.
    Type: Grant
    Filed: April 9, 1986
    Date of Patent: July 7, 1987
    Assignee: Petazon Inc.
    Inventors: Sandor Meszaros, Gisela Verzar-Petri, Klara Nyiredy-Mikita, Erno Tyihak, Szabolcs Nyiredy, Beat Meier, Otto Sticher, Karin Dallenbach-Toelke
  • Patent number: 4671871
    Abstract: The present invention relates to a chromatographic sheet and/or a system of chromatographic sheets for overpressured multilayer chromatography.One or more chromatographic sheets with sorbent layer are optionally sealed at their edges preferably by impregnation or coating with a polymer film and holed at the solvent inlet in adequate size and shape and they are optionally included in a system in single or multiple layers with or without a conventional chromatographic sheet sealed at its edges.
    Type: Grant
    Filed: August 19, 1986
    Date of Patent: June 9, 1987
    Assignee: Labor Muszeripari Muvek
    Inventors: Tibor Szekely, Erno Tyihak, Emil Mincsovics, Zsuzsa Remenyi nee Korodi, Laszlo Peterfi, Gabor Kemeny, Gabor Takacs
  • Patent number: 4671870
    Abstract: The invention relates to an apparatus for overpressured thin-layer chromatographic technique, comprising at least one carrier plate arranged adjacent a closed space, a sorbent layer arranged on the surface of said carrier plate, means for covering the surface of said sorbent layer under influence of overpressure generated in said closed space, a first inlet for admitting solvent to said sorbent layer, a second inlet for admitting overpressurizing medium into said closed space, a heating unit for altering temperature of said sorbent layer and a temperature control unit for energizing said heating unit. The apparatus according to the invention ensures improved efficiency of the chromatographic developments carried out under overpressure. By means of the apparatus chromatograms can be obtained with increasing speed of separation.
    Type: Grant
    Filed: April 18, 1985
    Date of Patent: June 9, 1987
    Inventors: Ildiko F. Tompa, Attila Nagy, Erno Tyihak, Szabolcs Nyiredy, Gizella V. Petri, Sandor Meszaros, Laszlo Szepesy, Laszlo Vida, Emil Mincsovics, Gabor Kemeny, Piroska Baranyi
  • Patent number: 4591524
    Abstract: An adsorbent layer (stationary phase) for a pressurized layer chromatographic apparatus, for the development of linear chromatogram, is sealed at the edges by impregnation. For the purpose of solvent control some of the adsorbent material is removed in one or several zones of the adsorbent layer near the place of solvent admission, or one or several baffle plates or wires are arranged behind the place(s) of sample application, or if necessary, the adsorbent layer is provided with a conventionally formed concentration zone in the area of the solvent admission. As a result of the impregnation, the migrating solvent composite does not escape at the edges of the adsorbent layer according to the invention in case of overpressure. As a result of the removal of adsorbent material, or the arrangement of baffles or wires, or the application of a concentration zone, the solvent migrates with a straight-line front.
    Type: Grant
    Filed: July 15, 1981
    Date of Patent: May 27, 1986
    Inventors: Erno Tyihak, Emil Mincsovics, Jozsef Knoll, Sandor Zoltan, Istvan Lak, Peter Tetenyi, Huba Kalasz, Janos Nagy
  • Patent number: 4590167
    Abstract: Thin-layer chromatography is employed to separate enantiomers of the general formula, ##STR1## in which C* represents an asymmetric center and the substituents R.sup.1, R.sup.2, and R.sup.3 are such that they supply the structural element ##STR2## for .alpha.-amino- or .alpha.-iminocarboxylic acids, particularly the well-known .alpha.-amino- or .alpha.-iminocarboxylic or for derivatives of such carboxylic acids, either of which contains no free thiol groups. In the thin-layer chromatographic separation operation a TLC plate is used which is coated with silica gel hydrophobicized by a silane derivative and which is further impregnated with an ionic compound of a divalent transition metal and a chiral selector. The mobile phase employed is a ternary mixture of a water-miscible alkanol, such as methanol, water, and acetonitrile, or a quaternary mixture of the latter ternary mixture to which a water-miscible cyclic ether, such as tetrahydrofuran, has been added.
    Type: Grant
    Filed: July 25, 1984
    Date of Patent: May 20, 1986
    Assignee: Degussa Aktiengesellschaft
    Inventors: Kurt Gunther, Jurgen Martens, Maren Schickedanz
  • Patent number: 4587020
    Abstract: A chromatographic plate comprising a support having a plurality of linear grooves engraved on the rear is disclosed. Each of said grooves have a uniform depth of a half or less as large as the thickness of the support and serves to guide a cutter. After the chromatographic development, the support may easily be cloven along the grooves into strips together with an adsorbent layer carried by the front of the support to give a sample holder for mass spectrometry.
    Type: Grant
    Filed: August 16, 1984
    Date of Patent: May 6, 1986
    Assignee: Shionogi & Company, Ltd.
    Inventors: Yuzo Nakagawa, Kouji Iwatani, Tetsuro Kadono
  • Patent number: 4582731
    Abstract: Solid films are deposited, or fine powders formed, by dissolving a solid material into a supercritical fluid solution at an elevated pressure and then rapidly expanding the solution through a short orifice into a region of relatively low pressure. This produces a molecular spray which is directed against a substrate to deposit a solid thin film thereon, or discharged into a collection chamber to collect a fine powder. Upon expansion and supersonic interaction with background gases in the low pressure region, any clusters of solvent are broken up and the solvent is vaporized and pumped away. Solute concentration in the solution is varied primarily by varying solution pressure to determine, together with flow rate, the rate of deposition and to control in part whether a film or powder is produced and the granularity of each. Solvent clustering and solute nucleation are controlled by manipulating the rate of expansion of the solution and the pressure of the lower pressure region.
    Type: Grant
    Filed: September 1, 1983
    Date of Patent: April 15, 1986
    Assignee: Battelle Memorial Institute
    Inventor: Richard D. Smith
  • Patent number: 4508624
    Abstract: Disclosed is a ceramic body for chromatography, which consists of a calcined molded body of alumina particles composed mainly of .alpha.-alumina, preferably containing a minor amount of .gamma.-alumina, and which has a narrow pore size distribution range.This ceramic body has no substantial adsorbing property and therefore, when it is used for use like to thin layer chromatography or gas chromatography, the tailing phenomenon is not caused to occur at all and a high separating capacity can be obtained stably.
    Type: Grant
    Filed: November 26, 1982
    Date of Patent: April 2, 1985
    Assignee: Kyoto Ceramic Co., Ltd.
    Inventor: Koichi Nagata
  • Patent number: 4486311
    Abstract: In packing gels of different activities together into a liquid chromatographic column, this invention provides a method which makes it possible to obtain a remarkably elevated separation performance by packing a gel of high activity in a layer at the outlet side of the column for a length within the range of 5 to 60% of the total packing length.
    Type: Grant
    Filed: March 14, 1984
    Date of Patent: December 4, 1984
    Assignee: Japan Exlan Company Limited
    Inventors: Shigeru Nakajima, Masahiko Ozaki
  • Patent number: 4469601
    Abstract: A column and detector are disclosed for two-dimensional column chromatography of a sample, in which the sample is injected close to a corner of a thin parallelepipedal column through which percolates a first solvent pumped at a controlled velocity. After a convenient time this flow is stopped and a stream of a second solvent is pumped at a controlled velocity in the perpendicular direction. Elution of the separated components is performed, the stream exiting from the column flows over a detector which monitors its composition at a large number of points, along the exit edge allowing the derivation of a two-dimensional chromatogram.
    Type: Grant
    Filed: September 7, 1982
    Date of Patent: September 4, 1984
    Assignee: Varex Corporation
    Inventors: Lois A. Beaver, Georges A. Guiochon
  • Patent number: 4468328
    Abstract: Droplet counter-current chromatography is utilized to isolate and purify 12-O-tetradecanoylphorbol-13-acetate (TPA), phorbol, and the diastereoisomer 4.alpha.-phorbol from croton oil. The stationary and mobile phases for the procedure are derived from an equilibrated mixture of hexane-diethylether-n-propanol-ethanol-water, the separated upper layer of which comprises the stationary phase and the bottom layer of which the mobile phase. The TPA and the phorbol isomers are obtained in exceptionally high purity by further treatment with liquid column chromatography and thin-layer chromatography.
    Type: Grant
    Filed: January 17, 1983
    Date of Patent: August 28, 1984
    Assignee: The Board of Trustees of the University of Ill.
    Inventors: Alan D. Kinghorn, Gary T. Marshall
  • Patent number: 4443339
    Abstract: The present invention relates to composite materials. A composite material is disclosed for the selective retention of chemical species from a fluid substance. The composite material comprises a support material, a permeable gel retained on the support material and, in the permeable gel, an active material capable of selectively retaining the chemical species.At least some of the permeable gel is enmeshed with the support material.A method for the preparation of the composite material is also disclosed.
    Type: Grant
    Filed: September 3, 1981
    Date of Patent: April 17, 1984
    Assignee: United Kingdom Atomic Energy Authority
    Inventor: Alan Rosevear
  • Patent number: 4438205
    Abstract: Sampling and analyzing at least one mixture of substances by slab chromatography or thin layer chromatography involves sampling the mixture on a non-adsorbent solid support using a sampling member to achieve precisely repeatable conditions, depositing an appropriate amount of the mixture to be analyzed on an edge zone of a chromatography plate, bringing the said edge of the chromatography plate into contact with a solvent or a mixture of solvents to cause the migration of the mixture on the chromatography plate and the separation of the constituents of the said mixture, and developing the said plate for the qualitative and/or quantitative analysis of the constituents of the mixture, by pressing that face of the support which bears the mixture against the chromatography plate until the mixture to be analyzed has essentially migrated entirely out of the abovementioned support.
    Type: Grant
    Filed: July 13, 1982
    Date of Patent: March 20, 1984
    Assignee: "L'Oreal"
    Inventors: Didier J. Saint-Leger, Andre Abrioux
  • Patent number: 4435504
    Abstract: Chromatographic immunoassay employing a specific binding pair member and a label conjugate which delineates a border whose distance from one end of the chromatograph relates to the amount of analyte present. By combining the label conjugate and sample in a solution and immunochromatographing the solution, or employing a combination of enzymes, one enzyme being the label and the other enzyme affixed to the chromatographic support, the position of the border defined by the label can be related to the amount of analyte in the sample solution.Preferably, an immunochromatograph is employed having both a specific binding pair member and an enzyme affixed to the support.
    Type: Grant
    Filed: July 15, 1982
    Date of Patent: March 6, 1984
    Assignee: Syva Company
    Inventors: Robert F. Zuk, David J. Litman
  • Patent number: 4428908
    Abstract: A radionuclide quality control test kit includes a disposable chromatography chamber. A premeasured amount of a solvent solution is provided in the chamber. A disposable test strip has spaced opposite first and second ends. The first end is immersible in the solvent solution in the chamber upon being spotted by a radiopharmaceutical to be tested to enable the solvent solution to ascend the strip to the second end whereat radiochemical impurities of the radiopharmaceutical migrating to the second end are radiologically countable to permit computation of such impurities.
    Type: Grant
    Filed: March 25, 1982
    Date of Patent: January 31, 1984
    Inventors: Sheldon J. Ashley, Meredith A. Ashley
  • Patent number: 4388193
    Abstract: This invention concerns chromatography in general, and more specifically to a method and apparatus for performing thin-layer chromatography without employing capillary suction, and further to a method wherein circular and anticircular chromatographic analysis can be performed simultaneously.
    Type: Grant
    Filed: November 25, 1980
    Date of Patent: June 14, 1983
    Inventor: Paul Buncak
  • Patent number: 4384958
    Abstract: There is disclosed a thin layer chromatography device comprising a transparent tube, a coating of adsorbent on the inside of the tube to provide a thin chromatography layer, one end of the tube narrowed down to form a neck with a score line thereon for breaking the neck, the other end of the tube being sealed to provide a hermetically sealed chromatography device, there being at least one small opening in the tube near the neck end of the tube for providing means to insert a sample into the tube on the thin chromatography layer and for providing means to form an air vent to the inside of the tube when the neck end is broken and placed in a solvent.
    Type: Grant
    Filed: February 26, 1982
    Date of Patent: May 24, 1983
    Assignee: Owens-Illinois, Inc.
    Inventors: Sandra M. Wisebaker, Paul L. White
  • Patent number: 4382000
    Abstract: There is disclosed a thin layer chromatography device comprising a transparent tube having a first open end adapted for sealing with a stopper, a cylindrical member such as a tube or rod having a diameter smaller than the tube and of a length at least about equal to that of the tube, the member adapted to fit concentrically within the tube, the outside surface of the member being adapted to receive a thin layer of adsorbent before assembly of the member inside the tube, a fitting at the first end of the tube, the fitting having an annular portion defining an opening adapted to receive and hold the member when the tube and member are assembled together to provide a hermetically sealed device before use, at least one sample positioning opening in the tube whereby, upon use of the device, a sample can be positioned on the outer surface of the member and whereby air can enter the interior of the tube.
    Type: Grant
    Filed: February 26, 1982
    Date of Patent: May 3, 1983
    Assignee: Owens-Illinois, Inc.
    Inventors: Sandra M. Wisebaker, Paul L. White
  • Patent number: 4377641
    Abstract: A method and apparatus for continuous extraction of an ingredient from a sample employs a container having a solvent therein selected for its ability to extract the ingredient. The sample is held against a porous substrate having a lower portion which is located below the sample and placed in the solvent, and an upper portion which is located above the sample and exposed to a selected atmosphere. In a continuous supply from the container, solvent is caused to ascend the substrate by capillary action, penetrate the sample, extract the ingredient therefrom, and continue to ascend the upper portion of the substrate where it evaporates, depositing the extracted ingredient thereon. The upper portion of the substrate containing the ingredient may then be removed.
    Type: Grant
    Filed: October 22, 1981
    Date of Patent: March 22, 1983
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Louis A. Dee, Mary E. Fiske
  • Patent number: 4348286
    Abstract: In thin layer chromatographic plates comprising adsorbent layers characterized by adsorptivity which increases from a first edge to the edge opposite, as, for example, in wedge layer plates, resolution is improved by development in the direction of increasing adsorptivity.
    Type: Grant
    Filed: July 17, 1981
    Date of Patent: September 7, 1982
    Assignee: Analtech, Incorporated
    Inventor: Herman R. Felton
  • Patent number: 4346001
    Abstract: A linear overpressured thin layer chromatographic apparatus comprises a base plate 3 supporting a sorbent layer 1 over which a membrane 4 is filled. The membrane 4 is externally pressurized by a fluid medium 10. A transparent cover plate 5 is fitted over the membrane 4, and there are sealed inlets 6, 7 passing through the cover plate 5 for the introduction of the mobile phase and the samples.
    Type: Grant
    Filed: June 12, 1981
    Date of Patent: August 24, 1982
    Assignee: Labor Muszeripari Muvek
    Inventors: Erno Tyihak, Emil Mincsovics, Sandor Dios, Gyula Horvath, Huba Kalasz, Janos Nagy, Ferenc Kormendi, Laszlo Kozma, Janos Borsos, Janos Kiss
  • Patent number: 4306977
    Abstract: A chromatography developing chamber for developing thin layer or paper chromatographic materials comprising an elongated sleeve closed at one end, open at the other end and having a peripheral wall therebetween, such as a cylindrical sample tube. A ledge projecting inwardly from a peripheral wall of the sleeve is positioned adjacent the closed end to provide a surface for supporting the chromatographic material in the chamber. A liquid elution solvent fills the chamber from the closed end to a level below the ledge such that the chromatographic material on the ledge is supported out of contact with the solvent during a first stage of developing. The ledge permits the material to be readily displaced therefrom to fall into the solvent during a second stage of developing. The material may be displaced from the ledge by vibration, as by tapping the chamber, or by magnetic means.
    Type: Grant
    Filed: December 1, 1980
    Date of Patent: December 22, 1981
    Assignee: The United States of America as represented by the Secretary of the Interior
    Inventor: Huo-Ping Pan
  • Patent number: 4292041
    Abstract: Thin layer chromatography is used to separate various surfactants. The support medium is silica gel on a glass or acrylamide plate. The developing solvent is chloroform/methanol/water. After drying, the surfactants are detected at extremely low levels with iodine vapor, rhodamine 6G in methanol or phosphomolybdic acid in ethanol/ether, or radiolabelled surfactant. A method is given for the separation of surfactants from proteins or glycoproteins or lipoproteins or polysaccharides, or lipopolysaccharides.
    Type: Grant
    Filed: November 2, 1979
    Date of Patent: September 29, 1981
    Assignee: Merck & Co., Inc.
    Inventor: W. Wardle Fullerton
  • Patent number: 4284587
    Abstract: A new radioenzymatic assay for catecholamines utilizing the catechol-O-methyl transferase transfer of a methyl group from a labeled methyl donor to the catecholamines followed by isolation of the O-methylated(.sup.3 H)catecholamine and the subsequent measurement of radioactivity.
    Type: Grant
    Filed: October 12, 1978
    Date of Patent: August 18, 1981
    Assignee: The Upjohn Company
    Inventors: Garland A. Johnson, Jacob D. Peuler
  • Patent number: 4273653
    Abstract: Microchromatographic system which consists of a test tube serving as developing chamber (2) and being closed by a stopper (3), and a thin-layer plate or foil in the form of a strip (1) fitting into the test tube, said plate or foil being coated in its lower quarter with a layer for concentration and purification (a) which merges without interruption into a thin-layer chromatographic separating layer (b) covering the remainder of the strip.
    Type: Grant
    Filed: February 19, 1980
    Date of Patent: June 16, 1981
    Assignee: Hoechst Aktiengesellschaft
    Inventor: Michael Uihlein
  • Patent number: 4272380
    Abstract: An improved method of thin layer chromatography and articles are provided for the detection of drugs involving extraction, concentration, transfer to a disc, development and detection. The method employs lipophilic dye containing disc shaped inserts impregnated with analytes or one or more standards. The discs are inserted in corresponding hollows on a thin layer chromatographic plate and eluted with a suitable solvent. As the solvent migrates, the dye is eluted from the disc and migrates as a spot with the solvent front which is thus visually developed with the dye.
    Type: Grant
    Filed: September 13, 1979
    Date of Patent: June 9, 1981
    Assignee: Analytical Systems, Inc.
    Inventor: Donald W. Jones
  • Patent number: 4272381
    Abstract: A device for spotting samples at spaced locations on the adsorbent surface of a TLC (thin-layer chromatography) plate has a base with an elevated, flat TLC plate supporting area and an adjacent stepped down solvent trough containing area separated by a step. A wicking plate, having a number of wick-holding wells, is adapted to be positioned over the trough with the wicks dipping in the trough and the upper ends of the wicks adapted to engage the adsorbent surface of a TLC plate lowered against them. A novel wick of porous polyethylene may be pre-loaded with sample and dried before being loaded into the wicking plate. The base has spaced extensions defining a cut-out over which the wicking plate can be laid for loading, being appropriately positioned by pins extending from one of its long sides engaging the step on the base. When reversed, the non-pin-containing long side of the wicking plate engages the step and positions it over the trough.
    Type: Grant
    Filed: October 22, 1979
    Date of Patent: June 9, 1981
    Assignee: Schleicher & Schuell, Inc.
    Inventors: Richard D. Kremer, Michael J. Siebengartner
  • Patent number: 4271021
    Abstract: A process for increasing the resistance to water of a chromatographic sorbent layer coated onto a support and comprising a binder of (a) salt(s) of (a) polyacrylic acid(s) and/or polymethacrylic acid(s), comprises treating the coated sorbent layer with an acid and then washing and drying the acid treated layers. The thus-prepared chromatographic materials are not only highly water resistant but also have an advantageously low impurity content.
    Type: Grant
    Filed: December 5, 1979
    Date of Patent: June 2, 1981
    Assignee: Merck Patent Gesellschaft mit Beschrankter Haftung
    Inventor: Heinz E. Hauck
  • Patent number: 4263144
    Abstract: A device and method are described for collecting and transferring particulate material. The device includes a housing with a porous member and means for connecting the housing to a vacuum attached thereto. A plunger, slidably mounted in the housing, opens and closes fluid-flow communication between the vacuum source and the porous member. In operation the porous member with a vacuum applied to one side thereof is contacted with first a porous filamentary filter and then with the particulate material. The particulate material detachably adheres to the filter and can be transferred to a collection area. The device and method of the invention are specifically suited for collecting and transferring adsorbent chromatographic fractions.
    Type: Grant
    Filed: December 10, 1979
    Date of Patent: April 21, 1981
    Assignee: The United States of America as represented by the Secretary of Agriculture
    Inventor: Steven G. Platt
  • Patent number: 4261835
    Abstract: This is an invention of paper chromatography and thin layer chromatography "baw-rar" (where "baw-rar" is Hebrew for separate) cones, hereon called PC and TLC cones, and other geometric shapes whose horizontal cross sections generally decrease in area as they are taken further from the base, with the adsorbent or absorbent layer decreasing in thickness from the base to the apex, to be used in PC and TLC work to reduce the horizontal and vertical spreading and diffusing of the developed spots. These will, for example, provide more easily and definitively determinable R.sub.f values, eliminate scraping of relatively large areas when scraping is necessary and increase the sensitivity of PC and TLC. The methods of use of the new PC and TLC cones are also disclosed herein.
    Type: Grant
    Filed: April 27, 1979
    Date of Patent: April 14, 1981
    Inventor: Samuel M. Creeger
  • Patent number: 4248904
    Abstract: A chemically inert, non-absorptive applicator sheet, a depression defined by a recessed portion of the applicator sheet, a transfer coating on at least a portion of a top surface of the applicator sheet, means for evaporating a solution of sample and carrier solvent deposited on the transfer coating, and a displacement mechanism for displacing a sample formed in the recess are disclosed. The depression in the applicator sheet may be formed by imposing a suction beneath the applicator sheet; and a displacement of a sample formed in the depression may be accomplished by introducing pressure beneath the applicator sheet.
    Type: Grant
    Filed: May 21, 1979
    Date of Patent: February 3, 1981
    Inventor: David C. Fenimore