A method for separating of at least two transition metals, the method comprising: injecting a feed solution into a chromatography column comprising a chromatographic support media, the feed solution comprising at least two transition metals; eluting the feed from the column in an elution cycle by flowing an eluent through the column, wherein a concentration of the eluent is reduced during the elution cycle prior to elution of at least one of the transition metals.

In an LC system using an ODS column (15) and UV detector (17), a cannabis-derived sample is analyzed by gradient elution using a phosphoric acid aqueous solution and phosphoric-acid-containing methanol. A control unit (3) regulates the openings of solenoid valves in a mixer (12) so that the increase rate of the mixture ratio of the phosphoric-acid-containing methanol in a second part of the analysis period is higher than in a first part. By this operation, ten active ingredients (including Total THC, Total CBD and CBN) contained in cannabis can be satisfactorily separated within an analysis time which is equal to or even shorter than approximately 30 minutes. Each ingredient separated by the column (15) is detected by the UV detector (17). An active ingredient identification processor (22) identifies the ten active ingredients based on the retention times of the peaks on a chromatogram created from the detection signals.

The present invention generally pertains to methods of characterizing charge variants of a protein of interest. In particular, the present invention pertains to the use of desalting size exclusion chromatography-reduced peptide mapping mass spectrometry to identify charge variants separated by capillary isoelectric focusing.

Apparatus for purifying a liquid comprising a target substance comprising at least two units arranged in series such that the feed stream of the second and any subsequent units comprises the product stream from a downstream unit, wherein each unit comprises specified components (i) to (vi), including a a switchable bypass assembly. Also claimed are the units and a flowpath assembly. The units may be essentially the same except for a device they contain, leading to advantages in terms of simplicity, cost and ease of operation, lower risk of operator error, easier maintenance and lower inventory of spare parts.

Buffer generators are described based on electrodialytic devices. The methods of using these devices can generate buffers for diverse applications, including separations, e.g., HPLC and ion chromatography. Also provided are chromatographic devices including the buffer generators, generally located upstream from a chromatography column, sample injector valve or both.

A method for removing coloration from a drug substance solution of protein preparation, in particular, antibody preparation, a method for preparing drug substance solution of protein preparations including it, as a part thereof, and highly concentrated, colorless drug substance solutions thereof are disclosed. The method removes terminal glycation products causing the coloration in the drug substance solution of protein preparation, in particular, antibody preparation, by anion-exchange chromatography, making it possible to provide colorless drug substance solutions.

Buffer generators are described based on electrodialytic devices. The methods of using these devices can generate buffers for diverse applications, including separations, e.g., HPLC and ion chromatography. Also provided are chromatographic devices including the buffer generators, generally located upstream from a chromatography column, sample injector valve or both.

Herein is reported a method for determining the presence of antibody-Fab-FcRn interaction in an antibody-Fc-FcRn complex influencing the in vivo half-life comprising the steps of a) determining the retention time of the antibody on an FcRn affinity chromatography column with a positive linear pH gradient elution in the presence of a first sodium chloride concentration, and b) determining the retention time of the antibody on an FcRn affinity chromatography column with a positive linear pH gradient elution in the presence of a second sodium chloride concentration, whereby the presence of antibody-Fab-FcRn interaction in an antibody-Fc-FcRn complex influencing the in vivo half-life is determined if the retention time determined in step a) and the retention time determined in step b) are substantially different.

A method of preparing a liquid mixture for use in a liquid chromatography system is provided. The mixture comprises one or more acids, one or more bases, one or more solvents and water, and the method comprises the steps of: calculating pH and/or solvent concentration at a particular time t from a user-determined gradient function; and, based on the values obtained, calculating percent acid, percent base, percent solvent and percent water in the liquid mixture at time t. A liquid chromatography system incorporating such method is also provided.

In an LC system using an ODS column (15) and UV detector (17), a cannabis-derived sample is analyzed by gradient elution using a phosphoric acid aqueous solution and phosphoric-acid-containing methanol. A control unit (3) regulates the openings of solenoid valves in a mixer (12) so that the increase rate of the mixture ratio of the phosphoric-acid-containing methanol in a second part of the analysis period is higher than in a first part. By this operation, ten active ingredients (including Total THC, Total CBI) and CEN) contained in cannabis can be satisfactorily separated within an analysis time which is equal to or even shorter than approximately 30 minutes. Each ingredient separated by the column (15) is detected by the UV detector (17). An active ingredient identification processor (22) identifies the ten active ingredients based on the retention times of the peaks on a chromatogram created from the detection signals.