Process and system for sample analysis
Components resolved in time by a separator accumulate in a sample cell and are analyzed by electromagnetic radiation-based spectroscopic techniques. The sample cell can be configured for multiple path absorption and can be heated. The separator can be a gas chromatograph or another suitable device, for example a distillation-based separator. The method and system described herein can include other mechanical elements, controls, procedures for handling background and sample data, protocols for species identification and/or quantification, automation, computer interfaces, algorithms, software or other features.
1. A method for analyzing a sample, comprising:
generating components from a sample;
acquiring spectral responses of the components over time; and
comparing current spectral responses to a background that changes with time and comprises previously acquired spectral responses to identify and/or quantify newly generated components;
wherein the current spectral responses and the previously acquired spectral responses are each averaged prior to the comparison.
2. The method of claim 1 , wherein generating components from the sample comprises providing the components using gas chromatography, liquid chromatography, affinity chromatography, supercritical fluid chromatography, ion exchange chromatography, distillation, fractional distillation, thermal desorption, pseudo distillation, thermogravimetric analysis, or a pyrolysis.
3. The method of claim 1 , wherein generating components from the sample comprises providing the components using gas chromatography.
4. The method of claim 1 , wherein acquiring the spectral responses of the components comprises collecting the responses in one or more of the following spectral regions millimeter, microwave, terahertz, infrared (including near-, mid- and/or far-infrared), visible, ultraviolet (UV) (including vacuum ultraviolet (VUV)), x-rays and/or gamma.
5. The method of claim 1 , wherein acquiring the spectral responses of the components comprises collecting the responses with a Fourier transform infrared spectrometry system.
6. The method of claim 1 , further comprising collecting at least one of the components in a sample cell and acquiring the spectral response of the components in the sample cell.
7. The method of claim 1 , wherein the current spectral responses and the previously acquired spectral responses are each averaged.
8. A method for analyzing a sample, comprising:
generating components from a sample;
acquiring spectral responses of the components over time; and
comparing current spectral responses to a background that changes with time and comprises previously acquired spectral responses to identify and/or quantify newly generated components;
wherein comparing the current spectral responses to the background comprises comparing current spectral response to spectral responses that were previously acquired by an amount defined by a skip time.
9. The method of claim 8 , wherein skip time is between 20 seconds and 2 minutes.
10. The method of claim 8 , wherein skip time is equal to or slightly longer than the time required for a chromatographic peak to elute.
11. The method of claim 8 , wherein the current spectral responses and the previously acquired spectral responses are each averaged prior to the comparison.
12. A method for analyzing a sample, comprising:
generating components from a sample;
acquiring spectral responses of the components over time; and
comparing current spectral responses to a background that changes with time and comprises previously acquired spectral responses to identify and/or quantify newly generated components;
wherein the current spectral responses and the previously acquired spectral responses are absorbance spectra that were calculated from averaged single beam sample spectra.
13. A sample analysis system, comprising:
a separator that provides components of a sample over time;
a spectrometry system that acquires spectral responses of the components; and
a computer system that compares current spectral responses to a background that changes with time and comprises previously acquired spectral responses to identify and/or quantify newly generated components; and
wherein the current spectral responses and the previously acquired spectral responses are absorbance spectra that were calculated from averaged single beam sample spectra.
14. A system as claimed in claim 13 , wherein the spectrometry system determines the spectral response of the components in the sample cell in one or more of the following spectral regions millimeter, microwave, terahertz, infrared (including near-, mid- and/or far-infrared), visible, ultraviolet (UV) (including vacuum ultraviolet (VUV)), x-rays and/or gamma.
15. A system as claimed in claim 13 , wherein the spectrometry system is a Fourier transform infrared spectrometry system.
16. A system as claimed in claim 13 , wherein the separator is a gas chromatography system, liquid chromatography system, affinity chromatography system, supercritical fluid chromatography system, ion exchange chromatography system, distillation system, fractional distillation system, thermal desorption system, pseudo distillation apparatus, thermogravimetric analysis instrument, or a pyrolysis instrument.
17. A system as claimed in claim 13 , wherein the separator is a gas chromatography system.
18. A system as claimed in claim 13 , wherein the current spectral responses and the previously acquired spectral responses are each averaged.
19. A sample analysis system, comprising:
a separator that provides components of a sample over time;
a spectrometry system that acquires spectral responses of the components; and
a computer system that compares current spectral responses to a background that changes with time and comprises previously acquired spectral responses to identify and/or quantify newly generated components;
wherein the computer system compares the current spectral responses to spectral responses that were previously acquired by an amount defined by skip time.
20. A system as claimed in claim 19 , wherein the skip time is between 20 seconds and 2 minutes.
21. A system as claimed in claim 19 ; wherein skip time is equal to or slightly longer than the time required for a chromatographic peak to elute.
22. A system as claimed in claim 19 , wherein the current spectral responses and the previously acquired spectral responses are absorbance spectra that were calculated from averaged single beam sample spectra.
23. A method for analyzing a sample, comprising:
generating components from a sample;
acquiring spectral responses of the components over time; and
comparing current spectral responses to a background that changes with time and comprises previously acquired spectral responses to identify and/or quantify newly generated components;
wherein generating components from the sample comprises providing components that are not completely separated.
24. A sample analysis system, comprising:
a separator that provides components of a sample over time;
a spectrometry system that acquires spectral responses of the components; and
a computer system that compares current spectral responses to a background that changes with time and comprises previously acquired spectral responses to identify and/or quantify newly generated components;
wherein components provided by the separator are not completely separated.