Method for measuring viscosity of protein solution
AssigneeChugai Seiyaku Kabushiki Kaisha
InventorsMasakazu Fukuda, Akira Hayasaka, Tomoyuki Igawa, Atsuhiko Maeda, Machiko Fujino
Life of this patent
Estimating the term…
Abstract
The inventors discovered that viscosity of a protein solution can be estimated by measuring the apparent particle size or apparent molecular weight by a small angle X-ray scattering (SAXS) method or X-ray solution scattering method, which enables measurement of small amounts of samples, and then correlating those measurement results with viscosity of the protein solution.
Claims89
-22. (canceled)
A method of determining viscosity, at a given temperature, of a protein solution of interest, the method comprising:
- (a) irradiating, at the given temperature, a sample of the protein solution of interest with X-ray to obtain a scattering pattern;
- (b) determining, from the scattering pattern, a value for a parameter selected from:
- apparent maximum particle diameter (Dmaxapp) of the protein in the sample, apparent particle radius of gyration (Rgapp) of the protein in the sample, and apparent molecular weight of the protein in the sample;
- and
- (c) using the value for the selected parameter to determine, from a predetermined calibration curve, viscosity at the given temperature of the protein solution of interest, wherein the predetermined calibration curve correlates:
- (i) viscosity, measured at the given temperature, of a sample of each of a plurality of different test solutions, each comprising a test protein, to
- (ii) a value for the selected parameter of each of the test solutions, measured at the given temperature;
- wherein the test proteins in the test solutions can be the same or different, and
- wherein the protein concentration of each of the test solutions and the protein concentration of the protein solution of interest are the same, and are within the range of 1 mg/mL to 100 mg/mL.
A method of determining viscosity, at a first temperature, of a protein solution of interest, the method comprising:
- (a) irradiating, at a second temperature, a sample of the protein solution of interest with X-ray to obtain a scattering pattern;
- (b) determining, from the scattering pattern, a value for a parameter selected from:
- apparent maximum particle diameter (Dmaxapp) of the protein in the sample, apparent particle radius of gyration (Rgapp) of the protein in the sample, and apparent molecular weight of the protein in the sample;
- and
- (c) using the value for the selected parameter to determine, from a predetermined calibration curve, viscosity at the first temperature of the protein solution of interest, wherein the predetermined calibration curve correlates:
- (i) viscosity, measured at the first temperature, of a sample of each of a plurality of different test solutions, each comprising a test protein, to
- (ii) a value for the selected parameter of each of the test solutions, measured at the second temperature;
- wherein the test proteins in the test solutions can be the same or different, and
- wherein the protein concentration of each of the test solutions and the protein concentration of the protein solution of interest are the same, and are within the range of 1 mg/mL to 100 mg/mL.
A method of predicting viscosity, at a given temperature, of a protein solution of interest having a first concentration of a protein, the method comprising:
- (a) irradiating, at the given temperature, a sample solution having a second concentration of the protein with X-ray to obtain a scattering pattern, wherein the sample solution and the protein solution of interest are identical except for protein concentration;
- (b) determining, from the scattering pattern, a value for a parameter selected from:
- apparent maximum particle diameter (Dmaxapp) of the protein in the sample solution, apparent particle radius of gyration (Rgapp) of the protein in the sample solution, and apparent molecular weight of the protein in the sample solution;
- and
- (c) using the value for the selected parameter to determine, from a predetermined calibration curve, viscosity at the given temperature of the protein solution of interest,
- wherein the predetermined calibration curve correlates, for each of a plurality of test solution/corresponding solution pairs:
- (i) a value for the selected parameter, measured at the given temperature, for the test solution, to
- (ii) viscosity, measured at the given temperature, of the corresponding solution,
- wherein each test solution comprises a test protein that can be the same or vary among the plurality of test solutions,
- wherein each test solution and its paired corresponding solution comprise the same test protein and are identical except for concentration of the test protein,
- wherein the concentration of test protein in all of the test solutions is the second concentration and the concentration of test protein in all of the corresponding solutions is the first concentration, and
- wherein the second concentration is a concentration in the range of 1 mg/mL to 100 mg/mL.
A method of predicting viscosity, at a first temperature, of a protein solution of interest having a first concentration of a protein, the method comprising:
- (a) irradiating, at a second temperature, a sample solution having a second concentration of the protein with X-ray to obtain a scattering pattern, wherein the sample solution and the protein solution of interest are identical except for protein concentration and temperature;
- (b) determining, from the scattering pattern, a value for a parameter selected from:
- apparent maximum particle diameter (Dmaxapp) of the protein in the sample solution, apparent particle radius of gyration (Rgapp) of the protein in the sample solution, and apparent molecular weight of the protein in the sample solution;
- and
- (c) using the value for the selected parameter to determine, from a predetermined calibration curve, viscosity of the protein solution of interest at the first temperature, wherein the predetermined calibration curve correlates, for each of a plurality of test solution/corresponding solution pairs:
- (i) a value for the selected parameter, measured at the second temperature, for the test solution, to
- (ii) viscosity, measured at the first temperature, of the corresponding solution,
- wherein each test solution comprises a test protein that can be the same or vary among the plurality of test solutions,
- wherein each test solution and its paired corresponding solution comprise the same test protein and are identical except for temperature and concentration of the test protein,
- wherein the concentration of test protein in all of the test solutions is the second concentration and the concentration of test protein in all of the corresponding solutions is the first concentration, and
- wherein the second concentration is a concentration in the range of 1 mg/mL to 100 mg/mL.
A modified antibody produced by substituting a portion of the amino acid residues of an original antibody with histidine (His) residues, whose amino acid residue at position 97 of the heavy chain according to the Kabat numbering system is not a His residue.
A modified antibody showing ion concentration-dependent antigen binding, which is produced by substituting a portion of the amino acid residues of an original antibody with other amino acids, wherein the amino acid residue at position 97 of the heavy chain according to the Kabat numbering system is not a His residue.
Dependencies are inferred from the claim text.