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.

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 GC sample carbon ladder is generated with the help of one or more of the following techniques: correction of solvent effects; fit analysis of the spectrum obtained for a target member of the carbon ladder and a reference spectrum; fit analysis of a sample carbon ladder in comparison with reference spectral features; constraints for proper order of elution; and/or inclusion of all members in a selected carbon ladder set.

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.

Exemplary embodiments provide methods, mediums, and systems for analyzing spectrometry and/or chromatography data, and in particular to techniques to improve the reproducibility of results of spectrographic and/or chromatographic experiments. For example, some embodiments provide techniques for normalizing mass spectrometry (MS) and/or liquid chromatography (LC) data across different experimental devices, allowing data from different cohorts to be directly compared. To this end, exemplary embodiments provide a reliable, reproducible target library usable across different platforms, laboratories, and users. One embodiment leverages statistical techniques to select experimental parameters configured to reduce or minimize the chance of misidentifying a target molecule. Another embodiment leverages the law of large numbers to produce a composite product ion spectrum usable across different experiments. The composite product ion spectrum allows regression curves to be generated, where the regression curves can be used to normalize an experimental mass spectrum.

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.

The invention relates to a method for controlling preparative liquid chromatography, comprising the following steps, at least a part of said steps being implemented by a computer comprising a processor and a display screen coupled to said processor: (a) selecting an analytical liquid chromatography method from among thin layer chromatography (TLC) and high performance liquid chromatography (HPLC), (b) inputting analytical liquid chromatography data obtained by the method selected at step (a) for a product to be purified, (c) accessing a table of separating tools available to the user to implement said preparative liquid chromatography, (d) from said analytical liquid chromatography data and table of available separating tools, selecting an optimal separating tool from said table and computing preparative liquid chromatography operating conditions for said selected separating tool.

Methods for transferring a separation procedure from a first chromatographic system to a second one are disclosed that involve substantially matching a pressure profile. In some such methods, a length, an area, and a particle size of a first column in the first system and a flow rate in the first separation procedure are identifiable. Some such methods also involve selecting a combination of a length, an area, and a particle size of a second column in the second system and a flow rate for the second separation procedure. These methods may involve calculating a target length, a target area, or a target particle size for the second column in the second system or a target flow rate for the second separation procedure.

Methods for transferring a carbon dioxide based separation procedure from a reference chromatographic system to a target chromatographic system involve alternative techniques for determining system pressure drops not attributable to the column. One technique involves leveraging experimental chromatography to develop a correction factor that is a function of at least one correction coefficient and at least one ratio of the differential analyte retention time to the retention time in the reference system. Another technique involves leveraging other experimental measurements of tubing pressure drops under various condition to develop a lookup table that can be used to identify likely tubing pressure drops in the target system. A third technique leverages knowledge of the separation procedure and the target system and the likely nature of the relevant flow to calculate tubing pressure drops in the target system.

A thermal desorption tube for chromatography and mass spectrometry analysis. The thermal desorption tube includes a sorbent and a plurality of focusing agents loaded at known, relative amounts onto the sorbent. Each focusing agent is a compound that chromatographically elutes within a retention time similar to a retention time of a target analyte and has a mass spectrum similar to a mass spectrum of the target analyte. The thermal desorption tube is configured to be further loaded with a sample having the target analyte.