Abstract: A method for the removal of a substance, which has a negative charge and which is present in an aqueous liquid (I). The method comprises the steps of: (i) contacting the liquid with an anion-exchanger (1) that comprises mixed mode anion-exchanging ligands in which there is a positively charged nitrogen allowing binding of the substance to the anion-exchanger; and (ii) desorbing said substance from said anion-exchanger. The characteristic feature is that (A) the mixed mode ligands have a thioether linkage within a distance of 1-7 atoms from their positively charged atom, and (B) the anion-exchanger (1) (i) is capable of binding the substance of interest in an aqueous reference liquid (II) at an ionic strength corresponding to 0.25 M NaCl, and (ii) permits in the pH interval 2-12 a maximal breakthrough capacity for the substance which is ?200% of the breakthrough capacity of the substance for Q-Sepharose Fast Flow (anion-exchanger 2).

Abstract: The present invention relates to a method of preparing an immobilised metal ion affinity chromatography (IMAC) adsorbent, which comprises to provide chromatography ligands comprised of alkylene diamine triacetic acid, or a derivative thereof, and coupling thereof to a carrier via nitrogen. In an advantageous embodiment, the alkylene diamine triacetic acid is ethylene diaminetriacetic acid (ED3A).

Abstract: The present invention is a method of purifying recombinant human serum albumin (rHSA) from a solution, which method comprises to subject a cell culture supernatant (CCS) comprising rHSA cation exchange on a bimodal high salt tolerant matrix; hydrophobic interaction chromatography (HIC); anion exchange; and recovering the purified rHSA. The bimodal high salt tolerant cation exchange matrix used enables performing a purification of a cell culture supernatant directly, in the sense that no further dilution thereof is necessary. Due to its high binding capacity, said bimodal cation exchange matrix also allows use of a smaller amount of matrix as compared to a corresponding conventional cation exchanger matrix. Accordingly, the present invention allows substantial savings as regards volumes and consequently operation costs.

Abstract: The present invention is a method of separating recombinant human serum albumin (rHSA) from low molecular weight contaminants in a liquid, which method comprises the steps of: (a) providing a separation medium, which includes anion-exchanging ligands coupled to a base matrix; and (b) contacting the liquid with the separation medium to adsorb the rHSA to the ligands. In one embodiment, the functional groups of the ligands are weak anion-exchanging groups, preferably secondary amines, and the density of ligands on the base matrix is relatively high.

Abstract: The invention relates to a method for removing a positively charged substance from an aqueous liquid (I) by contacting the liquid with a cation-exchanger (1), possibly followed by a subsequent desorption of said substance. The cation-exchanger is selected to be capable of (a) binding to said substance by cation-exchange in an aqueous liquid reference (II) at an ionic strength corresponding to 0.3 M NaCl and (b) permitting a break through capacity for said substance 3200%, such as 3300% or 3500%, of the break-through capacity of said substance for a reference cation-exchanger (2) containing sulphopropyl groups —CH2CH2CH2SO2O—. The cation exchange ligands have an at least bimodal function by comprising a cation exchanging group and a separate hydrogen-bonding atom. The invention also relates to a method for testing the appropriateness of a cation-exchanger for removing a substance from a liquid and novel cation exchangers.

Abstract: Method for the removal of a substance from an aqueous liquid by ion exchange comprising providing a liquid with said substance is present; providing an adsorption matrix which comprises at least two different ligands; contacting the liquid with the matrix under a period of time and conditions sufficient to allow adsorption of the substance to the matrix; and adding an eluent that desorbs the substance from the matrix. Each one of the ligands interacts with the substance during the adsorption step, and at least one of the ligands is charged and capable of ionic interaction with the substance. The method can be run as a cation or anion exchange. The substance desorption can be performed by adding an eluent comprising an increasing ionic strength. The invention also encompasses an adsorbent comprising at least two structurally different ligands, which interact with the same kind of substance when used in a separation procedure.

Abstract: A method for purifying a desired substance by separating from each other a substance (I) from a substance (II), one of which is the desired substance, both of which have affinity for the same ligand structure, and wherein substance (I) is smaller than substance (II). The method comprising the steps of: (i) providing substances I and II in a liquid; (ii) contacting the liquid with an adsorbent which selectively adsorbs substance I; (iii) recovering the desired substance; The adsorbent has (a) an interior part which carries a ligand structure that is capable of binding to substances I and II, and is accessible to substance I, and (b) an outer surface layer that does not adsorb substance II, and is more easily penetrated by substance I than by substance II.

Abstract: The present invention is a method of separating recombinant human serum albumin (rHSA) from low molecular weight contaminants in a liquid, which method comprises the steps of: (a) providing a separation medium, which includes anion-exchanging ligands coupled to a base matrix; and (b) contacting the liquid with the separation medium to adsorb the rHSA to the ligands. In one embodiment, the functional groups of the ligands are weak anion-exchanging groups, preferably secondary amines, and the density of ligands on the base matrix is relatively high.

Abstract: The present invention is a method of purifying recombinant human serum albumin (rHSA) from a solution, which method comprises to subject a cell culture supernatant (CCS) comprising rHSA cation exchange on a bimodal high salt tolerant matrix; hydrophobic interaction chromatography (HIC); anion exchange; and recovering the purified rHSA. The bimodal high salt tolerant cation exchange matrix used enables performing a purification of a cell culture supernatant directly, in the sense that no further dilution thereof is necessary. Due to its high binding capacity, said bimodal cation exchange matrix also allows use of a smaller amount of matrix as compared to a corresponding conventional cation exchanger matrix. Accordingly, the present invention allows substantial savings as regards volumes and consequently operation costs.

Abstract: Method for desalting an aqueous liquid containing a charged substance comprising the steps of: (i) contacting liquid (I) with an ion-exchanger (1) under conditions permitting binding between ion-exchanger and substance, said ion-exchanger comprising a base matrix carrying an ion-exchange ligand (Ligand 1) with the opposite charge compared to the substance, (ii) desorbing said substance from said ion-exchanger by the use of a liquid (liquid (II)). Wherein: (A) ion-exchanger (1) is an ion-exchanger: (a) that can bind the substance in an aqueous reference liquid at ionic strength corresponding to 0.1 M NaCl, preferably 0.25 M NaCl; and (b) permits a breakthrough capacity at the pH provided by liquid (I) which is more than 2 mg/ml of gel, at a breakthrough of 10% and linear flow velocity of 300 cm/h; and (B) in step (ii) the pH of liquid (11) is adjusted to a pH value where the charge difference between the substance, the ligand and/or the ion-exchanger is lowered.

Abstract: The invention relates to a method for removing a positively charged substance from an aqueous liquid (I) by contacting the liquid with a cation-exchanger (1), possibly followed by a subsequent desorption of said substance. The cation-exchanger is selected to be capable of (a) binding to said substance by cation-exchange in an aqueous liquid reference (II) at an ionic strength corresponding to 0.3 M NaCl and (b) permitting a break through capacity for said substance 3200%, such as 3300% or 3500%, of the break-through capacity of said substance for a reference cation-exchanger (2) containing sulphopropyl groups —CH2CH2CH2SO2O—. The cation exchange ligands have an at least bimodal function by comprising a cation exchanging group and a separate hydrogen-bonding atom. The invention also relates to a method for testing the appropriateness of a cation-exchanger for removing a substance from a liquid and novel cation exchangers.

Abstract: A method for the removal of a substance carrying a negative charge and being present in an aqueous liquid (I). The method comprises the steps of: (i) contacting the liquid with a matrix carrying a plurality of ligands comprising a positively charged structure and a hydrophobic structure, and (ii) desorbing the substance.

Abstract: Method for desalting an aqueous liquid containing a charged substance comprising the steps of: (i) contacting liquid (I) with an ion-exchanger (1) under conditions permitting binding between ion-exchanger and substance, said ion-exchanger comprising a base matrix carrying an ion-exchange ligand (Ligand 1) with the opposite charge compared to the substance, (ii) desorbing said substance from said ion-exchanger by the use of a liquid (liquid (II)). Wherein: (&Lgr;) ion-exchanger (1) is an ion-exchanger::(a) that can bind the substance in an aqueous reference liquid at an ionic strength corresponding to 0.1 M NaCl, preferably 0.25 M NaCl; and (b) permits a breakthrough capacity at the pH provided by liquid (I) which is more than 2 mg/ml of gel, at a breakthrough of 10% and linear flow velocity of 300 cm/h; and (B) in step (ii) the pH of liquid (II) is adjusted to a pH value where the charge difference between the substance, the ligand and/or the ion-exchanger is lowered.

Abstract: A method for the removal of a substance carrying a negative charge and being present in an aqueous liquid (I). The method comprises the steps of: (i) contacting the liquid with a matrix carrying a plurality of ligands comprising a positively charged structure and a hydrophobic structure, and (ii) desorbing the substance.

Abstract: Method for the removal of a substance from an aqueous liquid by ion exchange comprising providing a liquid with said substance is present; providing an adsorption matrix which comprises at least two different ligands; contacting the liquid with the matrix under a period of time and conditions sufficient to allow adsorption of the substance to the matrix; and adding an eluent that desorbs the substance from the matrix. Each one of the ligands interacts with the substance during the adsorption step, and at least one of the ligands is charged and capable of ionic interaction with the substance. The method can be run as a cation or anion exchange. The substance desorption can be performed by adding an eluent comprising an increasing ionic strength. The invention also encompasses an adsorbent comprising at least two structurally different ligands, which interact with the same kind of substance when used in a separation procedure.

Abstract: Process for separating off a peptide or a nucleic acid by an anion exchanger (I) characterized in that a) the anion exchanger (I) exhibits ligands, which (i) contain a primary, secondary or tertiary amino group and (ii) are covalently bound to an organic polymer (matrix), b) there on a carbon atom at a distance of 2 or 3 atoms away from an amino nitrogen in the ligands is a hydroxyl group or a primary, secondary or tertiary amino group, and c) the maximum elution ionic strength in the pH range 2-14 for at least one of the proteins transferrin, ovalbumin 1, ovalbumin 2, .beta.-lactoglobulin 1 and .beta.-lactoglobulin 2 on the anion exchanger is higher than the elution ionic strength required for a quaternary comparative ion exchanger.

Abstract: A method for purifying a plant protein comprises: (a) preparing a crude plant extract; (b) passing the crude plant extract with a first buffer solution through a guard column comprising a hydrophobic interaction chromatography medium of hydrophobicity sufficiently high to prevent tannins and polyphenols from eluting from the column in the presence of the buffer solution, but sufficiently low that a protein fraction elutes with the first buffer solution; (c) passing the protein fraction through a capture column coupled in series to the guard column, the capture column comprising a hydrophobic interaction chromatography medium of hydrophobicity sufficiently high to prevent the protein from eluting in the presence of the buffer solution; and (d) eluting the protein from the capture column as a purified fraction. Preferably the plant is miracle fruit, the protein is Miraculin, and the method comprises ion exchange chromatography and gel filtration chromatography of the purified fraction of the protein.