A first chromatogram is obtained by analyzing a second standard sample by size exclusion chromatography analysis using a first detector. Also, a second chromatogram is obtained by analyzing a solvent for the second standard sample by size exclusion chromatography analysis using the first detector. Then, from the difference between the first chromatogram and the second chromatogram, a third elution time in size exclusion chromatography analysis of the second standard sample using the first detector is determined.

An exemplary chromatographic alignment system accesses a target file including data representative of a plurality of chromatographic features detected from a first sample and a reference file including data representative of a plurality of chromatographic features detected from a second sample. The system identifies, based on the target and reference files, a distinct retention time offset value for each chromatographic feature included in a first subset of the plurality of chromatographic features detected from the first sample. The system determines, based on the identified distinct retention time offset values for the chromatographic features included in the first subset and on a machine learning model, a distinct predicted retention time offset value for each chromatographic feature included in a second subset of the plurality of chromatographic features detected from the first sample. The system assigns the distinct predicted retention time offset value for each chromatographic feature included in the second subset.

A process for identifying an unknown compound in a sample includes matching a peak in a primary Fourier Transform Infrared spectral region of the sample spectrum with reference spectra in the same spectral region to generate an initial list of potential candidates, based, for example on goodness of fit criteria. The initial list can be reduced by retention time information and/or global peak matching techniques that analyze the sample spectrum in regions outside the primary region.

A method for reducing the variability, as measured by relative standard deviation (RSD), of an analytical testing technique is provided. This improvement in RSD improves the confidence in the values obtained during field testing. The method includes incorporating a focusing agent into the sampling media, which permits providing sampling media such as thermal desorption tubes preloaded with the focusing agent.

An analysis system includes a separation system that provides compounds to a sample cell of a spectrometric system. The system analyzes spectral information from the spectrometric system by optimizing retention windows for the compounds and identifies quantities of the compounds by comparing spectral information within and outside the respective retention windows.

A method for reducing the variability, as measured by relative standard deviation (RSD), of an analytical testing technique is provided. This improvement in RSD improves the confidence in the values obtained during field testing. The method includes incorporating a focusing agent into the sampling media, which permits providing sampling media such as thermal desorption tubes preloaded with the focusing agent.

Before start of analysis, a user inputs pipe capacity difference relative to reference pipe capacity and separation conditions, such as a mobile phase flow rate. A control unit calculates retention time shift from the pipe capacity difference and the flow rate. The control unit controls sample injection and data processing units so as to start collection of chromatogram data when a correction time has passed from the time point of sample injection in the case in which the value of the retention time shift is a positive value, and to perform sample injection when a correction time has passed from the time point at which the collection of chromatogram data is started in the case in which the value of the retention time shift is a negative value. Retention time shift caused by difference in the pipe capacity is corrected even when the mobile phase flow rate is different.

The present invention relates to a computer implemented method (600) performed by a chromatography apparatus (400) configured to separate molecules, having varying size, from an eluent, the method comprising obtaining (610) reference data for a chromatography column of the chromatography apparatus, wherein the reference data is indicative of elution characteristics for a set of molecular sizes, obtaining (620) an elution progress measure and a corresponding quantitative measure indicative of a concentration of molecules in an eluate of the chromatograph) apparatus, estimating (630) a size measure indicative of molecular size of the molecules in the eluate, rendering (640) a representation (300) indicative of the quantitative measure and the size measure, controlling (650) a display to display the representation to a user of the chromatography apparatus.

A plurality of measured product ion spectra is produced using a DIA tandem mass spectrometry method. One or more product ions are retrieved from a spectral library of known compounds or one or more theoretical product ions are calculated for the known compounds of a database. For each known or theoretical product ion, an XIC is calculated from the measured product ion spectra. Measured XIC peaks above a threshold intensity are grouped for the known compounds producing a subset of known compounds. Known or theoretical retention times are retrieved or calculated for the subset of known compounds. A regression function is calculated to correct the known or theoretical retention times using the known or theoretical retention times of the subset of known compounds as the independent variables and the measured retention times of the measured XIC peak groups of the subset of known compounds as the dependent variables.

A process for identifying an unknown compound in a sample includes matching a peak in a primary Fourier Transform Infrared spectral region of the sample spectrum with reference spectra in the same spectral region to generate an initial list of potential candidates, based, for example on goodness of fit criteria. The initial list can be reduced by retention time information and/or global peak matching techniques that analyze the sample spectrum in regions outside the primary region.