The present invention relates to the field of protein characterization, and in particular to methods for identifying critical quality attributes of therapeutic proteins expressed in host cells by implementing a workflow including using a competitive binding assay with insufficient antigen followed by SCX-MS.

A gas chromatography guard column assembly is disclosed including a guard column having an inlet and an outlet. The guard column is disposed in a coil having a column coil aspect ratio of less than 15. A gas chromatography system is disclosed including an oven cavity, a heater assembly, an inlet, a guard column, an analytical column, and a detector. The guard column is in fluid communication with the inlet and is disposed in a guard column coil. The analytical column is in fluid communication with the guard column and is disposed in an analytical column coil. The detector is in fluid communication with the analytical column. The analytical column coil has an analytical column coil central axis aligned with a central axis of the heater assembly, and the guard column coil has a guard column coil central axis remote from the central axis of the heater assembly.

The disclosed system and method improve measurement of trace volatile chemicals, such as by Gas Chromatography (GC) and Gas Chromatography/Mass Spectrometry (GCMS). A first trapping system can include a plurality of capillary columns in series and a focusing column fluidly coupled to a first detector. The first trapping system can retain and separate compounds in a sample, including C3 hydrocarbons and compounds heavier than C3 hydrocarbons (e.g., up to C12 hydrocarbons, or compounds having a boiling point around 250° C.), and can transfer the compounds from the focusing column to the first detector. A second trapping system can receive compounds that the first trapping system does not retain, and can include a packed trap and two columns. The second trapping system can remove water from the sample and can separate and detect compounds including C2 hydrocarbons and Formaldehyde.

A combined analyzer includes a thermal analyzer, a trap, a gas chromatograph, a mass spectrometer, a first flow path to which a gas generated in the thermal analyzer is supplied, a second flow path that branches from the first flow path and is connected to the mass spectrometer, a third flow path that branches from the first flow path and is connected to the trap, a fourth flow path that connects the trap and a column included in the gas chromatograph, and a fifth flow path that connects the column and the mass spectrometer.

The invention relates to a system and micro monitor apparatus, a space-, time-, and cost-efficient device to concentrate, identify, and quantify organic compounds in gas environments. The invention further relates to a method centered on gas chromatography for identifying and quantifying organic compounds in gas environments, using air as the carrier gas, without the need for a compressed pre-bottled purified carrier gas.

A sample introduction device 10 includes a tube holding section 21 and a sample removing mechanism 40. The sample removing mechanism 40 removes a sample 6 in a sample tube 2 held by the tube holding section 21. Thus, in the sample introduction device 10, the sample 6 in the sample tube 2 held by the tube holding section 21 can be automatically removed. As a result, the operator no longer needs to perform an operation of taking out the sample 6 from the sample tube 2. Thus, a work load on the operator can be reduced.

The disclosed embodiments relate to the design of a preconcentrator system for preconcentrating air samples. This preconcentrator system includes a plurality of preconcentrators that preconcentrate the air samples prior to chemical analysis, and a delivery structure comprising a manifold that selectively routes a sample airflow to the plurality of concentrators so that the plurality of preconcentrators receive a sample airflow concurrently or individually.

The disclosed embodiments relate to the design of a preconcentrator system for preconcentrating air samples. This preconcentrator system includes a plurality of preconcentrators that preconcentrate the air samples prior to chemical analysis, and a delivery structure comprising a manifold that selectively routes a sample airflow to the plurality of concentrators so that the plurality of preconcentrators receive a sample airflow concurrently or individually.

A first mixer mixes solvents therein. A second mixer has a capacity different from that of the first mixer, and mixes solvents therein. A first separation column is associated with the first mixer. A second separation column is associated with the second mixer. A first valve enables switchover between a first communication state in which the first mixer and the first separation column communicate with a detector, and a second communication state in which the second mixer and the second separation column communicate with the detector. Only by switching the first valve, it is possible to switch between the first communication state and the second communication state. The internal capacity of a flow channel in the first communication state differs from that in the second communication state. Therefore, it is easy to perform analysis with different internal capacities.

The invention relates to a system and micro monitor apparatus, a space-, time-, and cost-efficient device to concentrate, identify, and quantify organic compounds in gas environments. The invention further relates to a method centered on gas chromatography for identifying and quantifying organic compounds in gas environments, using air as the carrier gas, without the need for a compressed pre-bottled purified carrier gas.