Classifications

• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
  • G01N30/00—Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography or field flow fractionation
  • G01N30/02—Column chromatography
  • G01N30/84—Preparation of the fraction to be distributed
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
  • G01N30/00—Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography or field flow fractionation
  • G01N30/02—Column chromatography
  • G01N30/84—Preparation of the fraction to be distributed
  • G01N2030/8411—Intermediate storage of effluent, including condensation on surface
  • G01N2030/8417—Intermediate storage of effluent, including condensation on surface the store moving as a whole, e.g. moving wire
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
  • G01N30/00—Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography or field flow fractionation
  • G01N30/02—Column chromatography
  • G01N30/62—Detectors specially adapted therefor
  • G01N30/72—Mass spectrometers
  • G01N30/728—Intermediate storage of effluent, including condensation on surface
  • G01N30/7286—Intermediate storage of effluent, including condensation on surface the store moving as a whole, e.g. moving wire

Definitions

• the invention relates to a method of and apparatus for analysing a sample, and particularly
• conveying means to convey a sample to an analyser.
• liquid mixtures containing various components dissolved or dispersed therein.
• apparatus comprising a mobile phase supply, a sampling device, a column and a
• UN detection has been found to be highly sensitive, accurate and simple to
• refractive index detection is used. Whilst it is a widely used method, it is a widely used method, it is a widely used method, it is a widely used method, it is a widely used method, it is a widely used method, it is a widely used method, it is a widely used method, it is a widely used method, it is a widely used method, it is a widely used method, it is a widely used method, it is a widely used method, it
• the components separated by chromatography are transported on a
• the nickel catalyst converts the carbon
• FID flame ionisation detector
• An object of the present invention is to provide improved methods and apparatus for
• an analytical apparatus comprising:
• conveying means operable to convey the sample between the supply means and the analysing means, wherein the conveying means comprises an oxidised surface layer which receives the sample.
• the property may be a physical property, such as viscosity or melting temperature, of the sample or a chemical property, such as the chemical composition of the sample.
• the sample may be components of a mixture which has been previously separated by chromatography.
• the analysing means may be an analysing chamber, preferably without the need for conversion steps known hitherto.
• the oxidised surface layer is in the form of a continuous surface film.
• the oxidised surface layer may be porous.
• the oxidised surface layer is preferably readily wettable by solvents, especially aqueous and non-aqueous solvents such as water and polar solvents.
• solvents especially aqueous and non-aqueous solvents such as water and polar solvents.
• polar solvents include alcohols, such as ethanol and propanol, and DMSO.
• the oxidised surface layer is readily wettable by hydrocarbons including aromatic and non-aromatic, substituted and non-substituted alkyls.
• the sample is applied to the conveying means without substantial diffusion along the conveying means.
• the conveying means may comprise a metal, the metal having an oxidised surface layer.
• the conveying means is a wire which has an oxidised surface layer.
• a tape of material or a disk of material may be used instead of the wire.
• a typical width of tape is 1.5mm, with a thickness
• chromatography comprising the steps of providing a conveyor, such as a metal wire or
• the conveying means such as wire or tape
• the layer is made of titanium and the layer is
• the oxidised titanium forms a continuous porous surface film on the
• Preoxidised titanium wire comprising an oxidised surface coating is
• Suitable metals comprising an oxidised surface layer include molybdenum,
• the conveying means such as wire or tape is preferably carried on a supply spool and the
• inventions may include drawing off the wire from the supply spool by means of a take up
• a motor such as a stepper motor, may be computer controlled to draw the wire or
• the invention preferably includes controlling the tension of the wire between the spools to maintain a substantially constant tension in
• the wire particularly when the wire is heated as set out below.
• a traverse mechanism may be provided to ensure that, for example, the tape/wire is
• conveying means may be moved by means of one or more rollers in
• means does not vary according to the amount of e.g. tape/wire on the take up spool.
• the apparatus of the the invention comprises an analyser chamber.
• tape or wire with the separated components of the mixture can be improved by providing a
• the separated components of the mixture may be supplied to the surface of the tape or wire
• the cone such as a titanium cone, comprising an oxidised surface coating
• the cone draws off surplus mixture by directing the surplus mixture
• oxidised layer on the surface of the cone improves the wettability of the cone and improves the ability of the cone to direct surplus mixture a a ⁇ from the wire or tape thus preventing
• the aperture and cone may be positioned so that a continuous stream of separated
• a strongly dispersive coating may be provided each side of the aperture providing the
• the conveyor such as wire or tape, may be subjected to heat prior to entry into the conveyor
• nebu ser may be used to spray the sample onto the conveying means
• the nebuhser is a heated nebuhser
• the distance between the nebuhser and the surface of the conveying means may be
• the nebuliser comprises an inner tube through which the sample is passed, an
• the outer tube may comprise
• heating means for preheating the gas and sample stream.
• Such means include vanes for causing the gas to rotate prior to, or after,
• the outside of the inner tube may be shaped, e.g. in the
• component on the conveyer or wire may be subjected to pyrolysis to convert the component
• the pyrolysis preferably taking place within or adjacent to the
• the pyrolysis may be effected by heating coils disposed adjacent
• the conveyor or wire or by induction heating or by other means such as laser heating are the conveyor or wire or by induction heating or by other means such as laser heating.
• the analyser chamber may be defined in a housing formed from a machineable glass or
• one or more gas chromatography detectors such as argon ionisation detectors,
• the potential of the anode is great enough, the electrons will have sufficient kinetic energy
• the metastable argon atom carries no charge but has an electron displaced to an
• the analyser chamber is preferably provided with a source of a noble gas, such as
• anode as argon, an anode, a cathode, a potential between anode and cathode, and a radioactive
• the radioactive source may be an alpha-particle emitter, such as Americium, or a
• beta-particle emitter such as Ni 6 ⁇ This form of sensor is very sensitive, and is universal in
• a change in current flowing between the electrodes indicates the presence of separated components within the analysis chamber. This may be
• inert gases such as helium, neon or krypton, or a mixture thereof, may be used
• the invention may include providing further means for analysis downstream of
• the method of the invention is particularly advantageous in that
• detectors such as Electron Capture, Phosphorous and Sulphur
• the argon ionisation detector may be omitted and one or more of the other detectors
• Such detectors operate on a different principle from that of argon detectors.
• ⁇ -ray source such as Ni 63 is used to produce electrons as ions.
• Sensors can be made to
• pulsed mode in which a pulsed potential is used.
• D.C. mode a constant electrode potential of a few volts is employed that is just
• an electron capturing molecule for example a molecule containing a halogen atom with
• Electron-capture detectors are extremely sensitive and are widely used in the analysis of
• electron capture detector combines the universality of the argon detector with the
• detector may be placed immediately downstream of the argon detector.
• means to neutralise the charge on the pyrolysed sample may be provided. This may be, for
• analysis chamber is an argon detector comprising a source
• noble gas such as argon
• an anode a cathode
• the conveyor method of supplying the separated components onto the conveyor, and the
• chamber housing may be as defined previously for the first and second aspects of the
• the radioactive source is an alpha-particle emitter, such as
• the separated components react with metastable argon in situ.
• the electrons emitted by the separated components are detected by the increase in current
• the argon gas once it has passed through the chamber, may be directed to an electron
• a still further aspect of the invention provides a seal for an aperture
• the seal may be for use with a conveyor which moves through it.
• the magnetisable particles may be iron, iron coated with latex, or other commercially
• the magnetisable particles are maintained in a sealing
• the particles are selected so that if any do escape into the analyser chamber(s),
• Another aspect of the invention provides a seal for an aperture comprising magnetic
• FIG. 1 is a diagrammatic representation of apparatus in accordance with the
• Figure 2 is a diagrammatic cross-section through a section of wire used to transport
• Figure 3 shows a detail of the wetting device for applying sample to a wire
• Figure 4 shows a schematic diagram of an embodiment of the invention
• Figure 5 is a schematic cross-section through a magnetic particle seal according to
• Figure 6 shows a schematic cross-section of an alternative wetting device for use
• FIG. 7 shows an inner tube for use with the nebuhser of Figure 6.
• a chromatography column 10 of known kind has its outlet 12 arranged
• the feeder pipe 14 receives solvent from the
• the lower end of the feeder pipe 14 is arranged
• the conveyor wire 16 is an oxidised titanium wire
• the wire 16 is wound on a
• the take-up spool 22 is driven by a stepper motor 24 under the control
• a device (not shown) may be provided for maintaining a constant tension in
• a heater 29 is arranged immediately downstream of the spool 20 which
• a heating device 34 such as heating coil or induction heating
• a pump 35 is used to reduce
• the wire passes through a detection unit 36 which defines
• the detection unit 36 is made, for example, from machineable
• the detection unit 36 forms a housing having entry and exit ports 40, 42 for the wire 16, an
• a heating device 48 such as a heating coil or an
• induction heating device is arranged in the chamber 38 immediately adjacent the wire 16.
• the detection unit housing carries electrodes 50, 51 and also carries a radioactive substance
• the Americium 52 emits a particles into the
• Nickel-63 can be used as a ⁇ -emitter.
• the heating device 48 pyrolyses the sample
• a typical flow rate of Argon of up to 50 ml/min
• the detector unit 36 operates as described earlier to
• the electrodes 50,51 of the detector are arranged in a detection circuit indicated generally
• the detection circuitry 54 responds to current flow between the electrodes 50.51 and provides an output signal to a visual display 56.
• display 56 may produce a graphical representation 58 of the relative quantities of the
• component sample 30 passes through only a single conversion step for measurement
• the pyrolysed component when mixed with the argon can be tested again after it
• FIG. 3 shows a preferred arrangement of the feeder pipe 14 which supplies solvent from
• Pipe 14 delivers solvent containing the separated components
• the pipe 14 is made of stainless steel.
• hydrophobic (dispersive) material such as PTFE
• Figure 4 shows an alternative embodiment of the invention. Wire 70 onto which sample 72
• the analyser chamber 80 is then drawn into the analyser chamber 80.
• the analyser chamber 80 is then drawn into the analyser chamber 80.
• an ionising source 82 such as Nickel- 63 or Americium
• an ionising source 82 such as Nickel- 63 or Americium
• the analysis chamber 80 therefore acts as an argon
• the sample 72 is directly bombarded with metastable argon and electrons
• the Figure also shows argon
• Figure 5 shows a cross-section through a magnetic particle seal according to the invention.
• Wire 90 passes through aperture 92 in wall 93. Magnets 94, 96 provide a magnetic field
• wire 90 helps to prevent ingress of contaminants through the aperture 92.
• Figure 6 shows a nebuliser 100 comprising an inner tube 102 through which the sample to
• An outer tube 104 around the inner tube 102 channels a supply of gas past heating elements 106 to a nozzle 108 where the sample and gas mix.
• a conveying means 1 12. such as wire or tape.
• Figure 7 shows a preferred arrangement of inner tube 102for causing the gas in the outer
• the inner tube 102 is shown to comprise an inner bore 120,
• the apparatus has a very high sensitivity due to, for example,
• the present invention is useful for detecting substances which are impossible to detect with
• the apparatus may be fully automated and made smaller

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• Physics & Mathematics (AREA)
• Health & Medical Sciences (AREA)
• Life Sciences & Earth Sciences (AREA)
• Chemical & Material Sciences (AREA)
• Analytical Chemistry (AREA)
• Biochemistry (AREA)
• General Health & Medical Sciences (AREA)
• General Physics & Mathematics (AREA)
• Immunology (AREA)
• Pathology (AREA)
• Sampling And Sample Adjustment (AREA)
• Other Investigation Or Analysis Of Materials By Electrical Means (AREA)
• Investigating Or Analysing Materials By Optical Means (AREA)
• Investigating Or Analyzing Non-Biological Materials By The Use Of Chemical Means (AREA)
• Treatment Of Liquids With Adsorbents In General (AREA)

Priority Applications (7)

Applications Claiming Priority (2)

Publications (2)

Family

ID=10823452

Family Applications (1)

Country Status (10)

Cited By (1)

Families Citing this family (8)

Family Cites Families (7)

• 1997
  • 1997-12-12 GB GBGB9726199.4A patent/GB9726199D0/en not_active Ceased
• 1998
  • 1998-12-10 ES ES98959020T patent/ES2202913T3/es not_active Expired - Lifetime
  • 1998-12-10 DE DE69814916T patent/DE69814916T2/de not_active Expired - Fee Related
  • 1998-12-10 AT AT98959020T patent/ATE241129T1/de not_active IP Right Cessation
  • 1998-12-10 JP JP2000539331A patent/JP3626683B2/ja not_active Expired - Fee Related
  • 1998-12-10 EP EP98959020A patent/EP1038164B1/en not_active Expired - Lifetime
  • 1998-12-10 AU AU14958/99A patent/AU747241B2/en not_active Ceased
  • 1998-12-10 US US09/581,467 patent/US6462334B1/en not_active Expired - Fee Related
  • 1998-12-10 CA CA002314135A patent/CA2314135A1/en not_active Abandoned
  • 1998-12-10 WO PCT/GB1998/003672 patent/WO1999031481A2/en not_active Ceased

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