The United States of America as Represented by the Department of Health

The United States of America as Represented by the Secretary of

The United States of America, as Represented by the Secretary, Department of Health and Human Services

Other

The United States of America as Represented by the Secretary of Health

The United States Government as Represented by the Secretary of the

The Government of the U.S. as Represented by the Secretary of the

Yoichiro Ito

Theodor Kolobow

Ying Ma

Hans J Cahnmann

Kazufusa Shinomiya

Adrian Weisz

Yoichi Shibusawa

Peter Carmeci

Lin Qi

Tian Y Zhang

Hisao Oka

Eiichi Kitazume

A plate apparatus for use in countercurrent chromatography is disclosed which comprises a disk shaped tube support () having a tube support pattern form in an upper surface () of the support and configured to accommodate at least one layer of fluid flow tubing (), wherein the pattern comprises at least one spiral groove () and at least one return path ().

Apparatus for countercurrent chromatography

A countercurrent chromatography apparatus includes a plurality of plates, at least one plate () having first and second interleaved spiral flow channels () therein. Each spiral flow channels () has a first end (I, I, I, I) near the central axis and a second ends (O, O, O, O) near the periphery. The outlet of the first channel (O) is connected to the inlet of the second channel (I) by a connecting channel (). Septa may be provided between the plates to connect the spiral channels of one plate to the spiral channels of the next plate.

Method and apparatus for countercurrent chromatography

Preparative-scale separations of chiral compounds were achieved by high-speed countercurrent chromatography (HSCCC) using a multilayer coil planet centrifuge equipped with a 325 mL capacity column. The separations were performed by two different procedures both utilizing a set of N-(3,5-introbenzoyl)-D,L-amino acids as test samples with N-dodecanoyl-L-proline-3,5-dimethylanilide as a chiral selector (Cs). The HSCCC separations were carried out with a two-phase solvent system composed of hexane/ethyl acetate/methanol/water where the chiral selector was added to the organic stationary phase. A second procedure using pH-zone-refining CCC yielded characteristic fused rectangular peaks in which the two isomers were resolved with less than 5% of overlap.

Chiral separation of enantiomers by high-speed countercurrent chromatography

Preparative-scale separations of chiral compounds were achieved by high-speed countercurrent chromatography (HSCCC) using a multilayer coil planet centrifuge equipped with a 325 mL capacity column. The separations were performed by two different procedures both utilizing a set of N-(3,5-dintrobenzoyl)-D,L-amino acids as test samples with N-dodecanoyl-L-proline-3,5-dimethylanilide as a chiral selector (Cs). The HSCCC separations were carried out with a two-phase solvent system composed of hexane/ethyl acetate/methanol/water where the chiral selector was added to the organic stationary phase. A second procedure using pH-zone-refining CCC yielded characteristic fused rectangular peaks in which the two isomers were resolved with less than 5% of overlap.

There are provided decorative articles, and methods of making decorative articles, by applying adhesive and coloring agent to a plant, such as a dandelion, the plant having a stalk and an achene assembly, the achene assembly including a receptacle and a plurality of pappus structures; and then drying the adhesive and coloring agent. Also provided are kits for use in such methods.

Decorative floral article

Separations of very hydrophilic organic compounds has now been achieved using countercurrent chromatography in which a ligand for the analytes of interest is used to enhance the partitioning of the polar species into the organic layer of an aqueous/organic solvent mixture. The compounds are separated according to their affinity for the ligand in the stationary organic phase. This method of affinity countercurrent chromatography can also be conducted in a pH-zone refining mode.

Separation of polar compounds by affinity countercurrent chromatography

The present invention provides a new method of pH-zone-refining countercurrent chromatography that can be operated in a manner analogous to displacement chromatography. The method uses a retainer base (acid) in the stationary phase to retain analytes in the column and a displacer acid (base) to elute the analytes in the decreasing (or increasing) order of pK.sub.a and hydrophobicity. The elution produces a train of highly concentrated rectangular solute peaks with minimum overlap. To use pH-zone refining CCC in a displacement mode, the mobile and stationary phases are switched. Thus, the original eluent becomes a retainer to retain analytes in the stationary phase, and the original retainer acid becomes a displacer to displace the analytes from the stationary phase to the mobile phase at the back of the solute bands. The present method provides a distinct advantage over the pH-zone-refining countercurrent chromatography in the normal mode in that the eluted compound is provided as a salt-free acid or base in an organic solvent which can easily be evaporated. Additionally, the displacement mode of pH-zone-refining countercurrent chromatography is amenable to a ligand-affinity separation which may cover a broader range of analytes including nonionizable compounds. As with the normal mode, the present method can be used on a preparative scale.

Displacement countercurrent chromatography

A cross-axis synchronous flow-through coil planet centrifuge is disclosed which provides changeability in the position of the coils relative to the axis of rotation of the centrifuge. The advantage of such a feature is to allow adjustment of the centrifugal force operating on the coils to accommodate different types of separations. The coils are arranged in columns which are mounted to column holders that in turn can be engaged to the rotary frame of the centrifuge in positions in which the column holders intersect and do not intersect the rotary frame axis.

Variable-position cross-axis synchronous coil planet centrifuge for

A method for concentrating a solute from a mixture by countercurrent chromatography, by introducing a stationary phase into a countercurrent chromatographic centrifuge, introducing a sample of a mixture containing a solute into the centrifuge, introducing a sufficient quantity of an elution peak sharpening agent into the centrifuge, introducing a mobile phase into the centrifuge, and performing countercurrent chromatographic centrifugation. The eluting fractions containing the concentrated solute are identified and collected.

Method for concentrating a solute by countercurrent chromatography

It has now been discovered that acidic or basic compounds may be purified using a new countercurrent chromatography technique. This technique utilizes two immiscible solvent phases, one being acidic and one being basic. The solutes partition between the phases and elute in contiguous, well-resolved, rectangularly shaped peaks in order of their partition coefficients. The fractions within any single peak have a substantially constant concentration. In addition to differing partition coefficients, the peaks also differ in pH, successively increasing in the case of a basic mobile phase and successively decreasing in the case of an acidic mobile phase. For this reason, the technique may be referred to as 'pH-zone-refining countercurrent chromatography.' The method of this invention provides certain advantages over previously known countercurrent chromatography techniques. First, the method permits one to load a sample as a suspension into the separation column. Additionally, the minimal degree of elution peak overlap permits one to separate mixtures of greater volume than before in any given column without loss of resolution. Thus, columns which are otherwise recommended for separations of mixtures up to a certain maximum size can be used in the method of this invention for separating mixtures up to ten times that size or greater.

pH-zone-refining countercurrent chromatography

A method of separating rare earth elements and compounds from mixtures containing the same which comprises separating the rare earth elements and compounds by means of rotational high speed countercurrent chromatography.

Separation of rare earth elements with high-speed countercurrent

The invention relates to an improved continuous countercurrent chromatography apparatus. The invention further relates to an improved method of countercurrent chromatography comprises filling a separation column with a first solvent, introducing into the column a sample solute to be separated, continuously pumping a second solvent into the column, the second solvent being substantially immiscible with the first solvent, maintaining the solvent flowing out of the column at a temperature effective to avoid clouding thereof, spectrophotometrically monitoring the temperature-maintained separating fractions flowing out of the column, and applying back-pressure to the solvent flowing into and out of the monitor.

Apparatus for countercurrent chromatography separations

A method for synthesizing N-bromoacetyl-3,3',5-triiodo-L-thyronine which involves subjecting 3,3', 5-triiodo-L-thyronine to a one-step bromacetylation reaction wherein 3,3', 5-triiodo-L-thyronine and bromoacetyl bromide are refluxed together in a solution of ethyl acetate. After formation the N-bromoacetyl-3,3'-triiodo-L-thyronine is purified by fractionation utilizing high speed countercurrent chromatography. Labeled N-bromoacetyl-3,3'-5-triiodo-L-thryonine may be made by a one-step bromacetylation reaction by reducing either [.sup.125 I]T.sub.3 or [.sup.14 C]T.sub.3 with bromoacetyl bromide.

Synthesis and characterization of

A type-XLL cross-axis synchronous flow-through coil planet centrifuge including exclusively left-handed column coils and a method of separating macromolecules utilizing the same. The exclusive use of left-handed column coils allows retention of the stationary phase when utilizing aqueous-aqueous two-phase solvent systems. The cross-axis synchronous flow-through coil planet centrifuge has been utilized to separate proteins utilizing an aqueous-aqueous polymer phase solvent system. Technical Field

Type-XLL cross-axis synchronous flow-through coil planet centrifuge for

A countercurrent chromatography apparatus and method where the column rotates about an axis spaced apart from, parallel to, and in the same radial plane as a radius extending from the central axis of revolution. The apparatus generates a unique force field which enables excellent separation.

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Bethesda, MD, United States of America

Yoichiro Ito