Interlacing to improve sampling of data when ramping parameters

Patent metadata

Field	Value
Publication number	US-9620342-B2
Application number	US-201314443936-A
Country	US
Kind code	B2
Filing date	Nov 21, 2013
Priority date	Dec 20, 2012
Publication date	Apr 11, 2017
Grant date	Apr 11, 2017

Abstract

Systems and methods are provided for interlacing ramped mass spectrometer parameter values during data acquisition. Ions from a sample are acquired within a cycle time, Ct, using a mass spectrometer. Within each Ct, two or more scans of the acquired ions are performed using two or more ramped values for a parameter of the mass spectrometer. When it is determined that scans for a desired range of ramped parameter values cannot be performed within Ct, the desired range of ramped values is divided into at least two interlaced groups of ramped values. The mass spectrometer is instructed to perform scans for each of the interlaced groups within two or more cycle times. Spectra from the scans for each of the at least two interlaced groups are combined. The ramped parameter values of the combined spectra have the desired range and the desired effective step size.

First claim

What is claimed is:

1. A system for interlacing ramped mass spectrometer parameter values during data acquisition in order to maintain a desired range and step size for the values, comprising:
a mass spectrometer that repeatedly acquires ions from a sample within a cycle time, Ct, and within each Ct performs two or more scans of the acquired ions using two or more ramped values for a parameter of the mass spectrometer, wherein each of the two or more scans occurs within a step time, St, and each of the two or more ramped values vary by a step size, Ss, and
a processor in communication with the mass spectrometer that
calculates if scans for a desired range of ramped values for the parameter can be performed within Ct using the desired range of ramped values, St, and Ss, and
if the scans for the desired range cannot be performed within Ct,
divides the desired range of ramped values into at least two interlaced groups of ramped values, wherein each of the ramped values in each of the at least two interlaced groups of ramped values vary by a step size of at least 2Ss,
instructs the mass spectrometer to perform scans for each of the at least two interlaced groups within two or more separate cycle times, and
combines spectra from the scans for each of the at least two interlaced groups producing combined spectra for the two or more separate cycle times that span the desired range and have an effective step size of Ss across the desired range.

2. The system of claim 1 , wherein within each Ct the mass spectrometer performs two or more scans of the acquired ions using two or more ramped values for a parameter of a fragmentation device of the mass spectrometer that affects fragmentation of the acquired ions.

3. The system of claim 1 , wherein the parameter comprises collision energy (CE) and the fragmentation device comprises a collision cell.

4. The system of claim 1 , wherein within each Ct the mass spectrometer performs two or more scans of the acquired ions using two or more ramped values for a parameter of a separation device of the mass spectrometer that affects separation of the acquired ions.

5. The system of claim 1 , wherein the parameter comprises a compensation voltage (CoV) and the separation device comprises a differential mobility (DMS) separation device.

6. A method for interlacing ramped mass spectrometer parameter values during data acquisition in order to maintain a desired range and step size for the values, comprising:
repeatedly acquiring ions from a sample within a cycle time, Ct, using a mass spectrometer and within each Ct performing two or more scans of the acquired ions using two or more ramped values for a parameter of the mass spectrometer, wherein each of the two or more scans occurs within a step time, St, and each of the two or more ramped values vary by a step size, Ss,
calculating if scans for a desired range of ramped values for the parameter can be performed within Ct using the desired range of ramped values, St, and Ss and using a processor, and
if the scans for the desired range cannot be performed within Ct,
dividing the desired range of ramped values into at least two interlaced groups of ramped values using the processor, wherein each of the ramped values in each of the at least two interlaced groups of ramped values vary by a step size of at least 2Ss,
instructing the mass spectrometer to perform scans for each of the at least two interlaced groups within two or more separate cycle times using the processor, and
combining spectra from the scans for each of the at least two interlaced groups using the processor producing combined spectra for the two or more separate cycle times that span the desired range and have an effective step size of Ss across the desired range.

7. The method of claim 6 , wherein within each Ct the mass spectrometer performs two or more scans of the acquired ions using two or more ramped values for a parameter of a fragmentation device of the mass spectrometer that affects fragmentation of the acquired ions.

8. The method of claim 6 , wherein the parameter comprises collision energy (CE) and the fragmentation device comprises a collision cell.

9. The method of claim 6 , wherein within each Ct the mass spectrometer performs two or more scans of the acquired ions using two or more ramped values for a parameter of a separation device of the mass spectrometer that affects separation of the acquired ions.

10. The method of claim 6 , wherein the parameter comprises a compensation voltage (CoV) and the separation device comprises a differential mobility (DMS) separation device.

11. A computer program product, comprising a non-transitory and tangible computer-readable storage medium whose contents include a program with instructions being executed on a processor so as to perform a method for interlacing ramped mass spectrometer parameter values during data acquisition in order to maintain a desired range and step size for the values, the method comprising:
providing a system, wherein the system comprises one or more distinct software modules, and wherein the distinct software modules comprise a control module and an analysis module;
instructing a mass spectrometer to repeatedly acquire ions from a sample within a cycle time, Ct, and within each Ct to perform two or more scans of the acquired ions using two or more ramped values for a parameter of the mass spectrometer using the control module, wherein each of the two or more scans occurs within a step time, St, and each of the two or more ramped values vary by a step size, Ss,
calculating if scans for a desired range of ramped values for the parameter can be performed within Ct using the desired range of ramped values, St, and Ss and using the control module, and
if the scans for the desired range cannot be performed within Ct,
dividing the desired range of ramped values into at least two interlaced groups of ramped values using the analysis module, wherein each of the ramped values in each of the at least two interlaced groups of ramped values vary by a step size of at least 2Ss,
instructing the mass spectrometer to perform scans for each of the at least two interlaced groups within two or more separate cycle times using the control module, and
combining spectra from the scans for each of the at least two interlaced groups using the analysis module producing combined spectra for the two or more separate cycle times that span the desired range and have an effective step size of Ss across the desired range.

12. The computer program product of claim 11 , wherein within each Ct the mass spectrometer performs two or more scans of the acquired ions using two or more ramped values for a parameter of a fragmentation device of the mass spectrometer that affects fragmentation of the acquired ions.

13. The computer program product of claim 11 , wherein the parameter comprises collision energy (CE) and the fragmentation device comprises a collision cell.

14. The computer program product of claim 11 , wherein within each Ct the mass spectrometer performs two or more scans of the acquired ions using two or more ramped values for a parameter of a separation device of the mass spectrometer that affects separation of the acquired ions.

15. The computer program product of claim 11 , wherein the parameter comprises a compensation voltage (CoV) and the separation device comprises a differential mobility (DMS) separation device.

Assignees

• Dh Technologies Dev Pte Ltd

Inventors

• Cox David Michael

Classifications

• H01J49/26

  Mass spectrometers or separator tubes · CPC title

• H01J49/0031 Primary

  Step by step routines describing the use of the apparatus (H01J49/0081 takes precedence) · CPC title

• H01J49/004

  Combinations of spectrometers, tandem spectrometers, e.g. MS/MS, MSn · CPC title

• H01J49/0036 Primary

  Step by step routines describing the handling of the data generated during a measurement · CPC title