US5459677A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Calibration transfer for analytical instruments
Assignee: University of Washington
•
Filing: 1991-06-24
•
Granted: 1995-10-17
•
Expires: 2011-06-24
Abstract
Abstract A technique for transferring a multivariant calibration model from a reference analytical instrument to a target analytical instrument that may be a different instrument, or the same instrument at a later time. In a "direct" approach, a plurality of transfer samples are selected, and a plurality of measurements are made for each transfer sample using the reference instrument, producing a reference instrument response for each sample. These measurements are repeated for the target instrument, to produce a target instrument response for each transfer sample. One then generates transfer coefficients capable of performing a multivariate estimation of the reference instrument responses for the transfer samples from the target instrument responses for those samples. The transfer coefficients may then be used to convert a target instrument response for an unknown sample into the equivalent response for the reference instrument. In an important "piecewise" variation, the transfer coefficients comprise a plurality of estimation coefficients for estimating each reference data value from more-than-one but less-than-all target data values. "Classical" and "inverse" transfer techniques are also described, wherein target instrument responses for the transfer samples are combined with reference instrument responses for the full set of calibration samples, to derive a multivariate prediction model for the target instrument.
Inventors
- 👤 Bruce R. Kowalski
- 👤 David J. Veltkamp
- 👤 Yong D. Wang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 19:07
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/17; G01N21/25; G01N21/27; G01N21/274; G01N30/00; G01N30/02; G01N30/86; G01N30/8665; G01N30/8672; G01N2030/022; G01N2030/025; G01N30/62; G01N2030/626
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
155 words
A method of producing a multivariate prediction model for predicting a property of a sample using a target spectrometer, based in part upon data measured by a reference spectrometer, the method comprising: producing property data by measuring said property for each of a plurality of calibration samples; for each calibration sample, producing a reference spectrometer response by making a plurality of measurements using the reference spectrometer; for each transfer sample in a subset of the calibration samples, producing a target spectrometer response by making a plurality of measurements using the target spectrometer; using the reference spectrometer responses for the calibration samples, the target spectrometer responses for the transfer samples, and the property data, producing estimates of the responses of the target spectrometer to the calibration samples; and producing a multivariate prediction model for the target spectrometer by combining the estimates of the responses of the target spectrometer to the calibration samples with the property data.
Claim 2
Independent Claim
155 words
A method of producing a multivariate prediction model for predicting a property of a sample using a target spectrometer, based in part upon data measured by a reference spectrometer, the method comprising: producing property data by measuring said property for each of a plurality of calibration samples; for each calibration sample, producing a reference spectrometer response by making a plurality of measurements using the reference spectrometer; for each transfer sample in a subset of the calibration samples, producing a target spectrometer response by making a plurality of measurements using the target spectrometer; using the reference spectrometer responses for the calibration samples, the target spectrometer responses for the transfer samples, and the property data, producing estimates of the responses of the target spectrometer to the calibration samples; and producing a multivariate prediction model for the target spectrometer by combining the estimates of the responses of the target spectrometer to the calibration samples with the property data.
Claim 3
Dependent Claim
50 words
The method of claim 1, comprising the further steps of producing a target spectrometer response for an unknown sample using the target spectrometer, and predicting said property for the unknown sample by combining the multivariate prediction model for the target spectrometer with the target spectrometer response for the unknown sample.
Claim 4
Dependent Claim
90 words
The method of claim 1, wherein the step of producing estimates comprises determining R.sub.1 +CC.sup.-+ (R.sub.2 -R.sub.1) where R 1 is a matrix formed from the reference spectrometer responses for the calibration samples, R 1 is a matrix formed from the reference spectrometer responses for the transfer samples, R 2 is a matrix formed from the target spectrometer responses for the transfer samples, C is the property data for the calibration samples, and C -+ is the pseudoinverse of a matrix formed from the property data for the transfer samples.
Claim 5
Dependent Claim
50 words
The method of claim 3, comprising the further steps of producing a target spectrometer response for an unknown sample using the target spectrometer, and predicting said property for the unknown sample by combining the multivariate prediction model for the target spectrometer with the target spectrometer response for the unknown sample.
Claim 6
Independent Claim
152 words
A method of producing a multivariate prediction model for predicting a property of a sample using a target spectrometer, based in part upon data measured by a reference spectrometer, the method comprising: producing property data by measuring said property for each of a plurality of calibration samples; for each calibration sample, producing a reference spectrometer response making a plurality of measurements using the reference spectrometer; for each transfer sample in a subset of the calibration samples, producing a target spectrometer response by making a plurality of measurements using the target spectrometer; producing a multivariate prediction model for the reference spectrometer by using the reference spectrometer responses for the calibration samples the property data; and using the reference spectrometer responses for the transfer samples, the target spectrometer responses for the transfer samples, the multivariate prediction model for the reference spectrometer, and the property data, producing a multivariate prediction model for the target spectrometer.
Claim 7
Independent Claim
152 words
A method of producing a multivariate prediction model for predicting a property of a sample using a target spectrometer, based in part upon data measured by a reference spectrometer, the method comprising: producing property data by measuring said property for each of a plurality of calibration samples; for each calibration sample, producing a reference spectrometer response making a plurality of measurements using the reference spectrometer; for each transfer sample in a subset of the calibration samples, producing a target spectrometer response by making a plurality of measurements using the target spectrometer; producing a multivariate prediction model for the reference spectrometer by using the reference spectrometer responses for the calibration samples the property data; and using the reference spectrometer responses for the transfer samples, the target spectrometer responses for the transfer samples, the multivariate prediction model for the reference spectrometer, and the property data, producing a multivariate prediction model for the target spectrometer.
Claim 8
Dependent Claim
52 words
To the method of claim 5, comprising the further steps of producing a target spectrometer response for an unknown sample by using the target spectrometer, and predicting said property for the unknown sample by combining the multivariate prediction model for the target spectrometer with the target spectrometer response for the unknown sample.
Claim 9
Dependent Claim
86 words
The method of claim 5, wherein the multivariate prediction model for the target spectrometer is determined as follows b.sub.1 +(R.sub.2.sup.+ -R.sub.1.sup.+)c.sup.- where b 1 is the multivariate prediction model for the reference spectrometer, R 1 + is the inverse of a matrix formed from the reference spectrometer responses for the transfer samples, R 2 + is the inverse of a matrix formed from the target spectrometer responses for the transfer samples, and c - is a matrix formed from the property data for the transfer samples.
Claim 10
Dependent Claim
50 words
The method of claim 7, comprising the further steps of producing a target spectrometer response for an unknown sample using the target spectrometer, and predicting said property for the unknown sample by combining the multivariate prediction model for the target spectrometer with the target spectrometer response for the unknown sample.
Claim 11
Independent Claim
175 words
A method of using a target spectrometer to perform a plurality of measurements on an unknown sample so as to produce an estimate of a reference spectrometer response for the unknown sample, the reference spectrometer response comprising values that would have been obtained by performing said plurality of measurements on the unknown sample using a reference spectrometer, the method comprising: providing a plurality of transfer samples; producing a reference spectrometer response for each transfer sample, by making a plurality of measurements using the reference spectrometer; producing a target spectrometer response for each transfer sample, by making a plurality of measurements using the target spectrometer; producing transfer coefficients for performing a multivariate estimation of the reference spectrometer responses for the transfer samples from the target spectrometer responses for the transfer samples; producing a target spectrometer response for the unknown sample, by making a plurality of measurements using the target spectrometer; and converting the target spectrometer response for the unknown sample into an estimate of the reference spectrometer response for the unknown sample, using the transfer coefficients.
Claim 12
Independent Claim
175 words
A method of using a target spectrometer to perform a plurality of measurements on an unknown sample so as to produce an estimate of a reference spectrometer response for the unknown sample, the reference spectrometer response comprising values that would have been obtained by performing said plurality of measurements on the unknown sample using a reference spectrometer, the method comprising: providing a plurality of transfer samples; producing a reference spectrometer response for each transfer sample, by making a plurality of measurements using the reference spectrometer; producing a target spectrometer response for each transfer sample, by making a plurality of measurements using the target spectrometer; producing transfer coefficients for performing a multivariate estimation of the reference spectrometer responses for the transfer samples from the target spectrometer responses for the transfer samples; producing a target spectrometer response for the unknown sample, by making a plurality of measurements using the target spectrometer; and converting the target spectrometer response for the unknown sample into an estimate of the reference spectrometer response for the unknown sample, using the transfer coefficients.
Claim 13
Dependent Claim
76 words
The method of claim 9, wherein each reference spectrometer response comprises a reference data value for each of M measurements made using the reference spectrometer, wherein each target spectrometer response comprises a target data value for each of M measurements made using the target spectrometer, and wherein the transfer coefficients comprise a plurality of estimation coefficients for estimating each reference data value from a window comprising a plurality of substantially less than M target data values.
Claim 14
Dependent Claim
43 words
The method of claim 10, wherein each reference spectrometer response includes one or more nonlinear functions of the measurements made using the reference spectrometer, and wherein each target spectrometer response includes the same nonlinear functions of the measurements made using the target spectrometer.
Claim 15
Dependent Claim
52 words
The method of claim 9, wherein the transfer coefficients F are produced by determining: F=R.sub.2 +R.sub.1 where R 2 + is the inverse of a matrix formed from the target spectrometer responses for the transfer samples of R 1 is a matrix formed from the reference spectrometer response for the transfer samples.
Claim 16
Dependent Claim
30 words
The method of claim 9, wherein each reference spectrometer response and each target spectrometer response comprises a spectrum comprising a plurality of absorbance values at a corresponding plurality of wavelengths.
Claim 17
Dependent Claim
16 words
The method of claim 9, wherein the target spectrometer and the reference spectrometer are different spectrometers.
Claim 18
Dependent Claim
76 words
The method of claim 14, wherein each reference spectrometer response comprises a reference data value for each of M measurements made using the reference spectrometer, wherein each target spectrometer response comprises a target data value for each of M measurements made using the target spectrometer, and wherein the transfer coefficients comprise a plurality of estimation coefficients for estimating each reference data value from a window comprising a plurality of substantially less than M target data values.
Claim 19
Dependent Claim
52 words
The method of claim 14, wherein the transfer coefficients F are produced by determining F=R.sub.2 +R.sub.1 where R 2 + is the pseudoinverse of a matrix formed from the target spectrometer responses for the transfer samples and R 1 is a matrix formed from the reference spectrometer responses for the transfer samples.
Claim 20
Dependent Claim
108 words
The method of claim 9, comprising the further steps of: providing a plurality of calibration samples, the calibration samples including the transfer samples plus additional samples; producing a reference spectrometer response for each calibration sample, by making a plurality of measurements using the reference spectrometer; producing property data by measuring a property for each calibration sample; producing a multivariate prediction model for the reference spectrometer, using the reference spectrometer responses for the calibration samples and the property data; and predicting said property for the unknown sample by combining the estimate of the reference spectrometer response for the unknown sample with the multivariate prediction model for the reference spectrometer.
Claim 21
Dependent Claim
19 words
The method of claim 17, wherein said property is a concentration of an analyte included in the calibration samples.
References Cited (Backward Citations)
US3975727A
Cited
US4587624A
Cited
US4660151A
Cited
US4866644A
Cited
US5016203A
Cited
US4916645A
Cited
US4864842A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-10-16 | 1999-04-17 | 1999-10-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-10-16 | 2003-04-17 | 2003-10-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-10-16 | 2007-04-17 | 2007-10-17 | $7700.00 | Window Closed / Lapsed |