US3766048A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Analysis of polymer mixtures in solution utilizing electrophoretic light scattering apparatus
Assignee: University of Illinois at Urbana-Champaign
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Filing: 1972-11-24
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Granted: 1973-10-16
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Expires: 1992-11-24
Abstract
Abstract An electrophoretic light scattering apparatus for determining the electrophoretic mobility and diffusion coefficient of a macromolecular polymer in solution is disclosed. More particularly, the charged macromolecules are driven through the solution by an electric field developed between two charged electrodes in a modified electrophoretic cell. The electric field is alternately enabled and disabled during the determination to prevent excessive heat build-up in the solution and the resultant convection of macromolecules which would distort the measurements. A laser provides an incident light beam which is passed through the cell perpendicular to the direction of the macromolecule flow so that the autocorrelation function or, alternatively, the frequency spectrum of the light scattered from the macromolecules can be observed at low scattering angles. The scattered light, in addition to having a frequency distribution curve proportional to the diffusion coefficient of the macromolecules, is Doppler shifted by an amount proportional to the electrophoretic mobility of the macromolecule in the scattering region. Because each species of polymers has a unique electrophoretic mobility and hence Doppler shift, the apparatus is useful in quantitatively analyzing a mixture of several different polymers in solution (e.g., life-like enzymes such as blood) to identify the polymers and their relative concentrations.
Inventors
- 👤 W Flygare
- 👤 B Ware
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 22:38
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/26; G01N27/416; G01N27/447; G01N27/44704; G01N27/44717; G01N27/44721; G01N15/00; G01N2015/0003
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
49 words
An electrophoretic light scattering apparatus in accordance with claim 1 including pulse means developing a pulse train for alternately enabling and disabling said electric field during the determination of said electrophoretic mobilities and said diffusion coefficients to reduce heat build-up in the solution thereby preventing convection of said macromolecules.
Claim 2
Dependent Claim
47 words
An electrophoretic light scattering apparatus in accordance with claim 2 wherein said detector means includes trigger means for enabling said detector means a predetermined time interval after said electric field is enabled to allow said macromolecules to reach a steady state before said scattered light is analyzed.
Claim 3
Dependent Claim
46 words
An electrophoretic light scattering apparatus in accordance with claim 2 wherein said pulse means includes means for alternating the polarity of said pulses, said electric field being periodically reversed responsive to said pulses for preventing the formation of concentration gradients due to accumulation of said macromolecules.
Claim 4
Dependent Claim
45 words
An electrophoretic light scattering apparatus in accordance with claim 1 wherein said detector means includes photomultiplier means for detecting and heterodyning said scattered light with said incident light beam to permit frequency analysis of said scattered light at beat frequencies in the audio frequency range.
Claim 5
Dependent Claim
63 words
An electrophoretic light scattering apparatus in accordance with claim 1 wherein said detector means includes autocorrelation means and averaging means, said autocorrelation means determining the autocorrelation function of said scattered light during successive intervals comprising data points, said averaging means holding the first data point and multiplying it by each successive data point so that the autocorrelation function is repeatedly calculated and averaged.
Claim 6
Dependent Claim
65 words
An electrophoretic light scattering apparatus in accordance with claim 1 wherein said detector means includes spectrum analyzer means and averaging means, said spectrum analyzer means determining the frequency spectrum of said scattered light during successive intervals comprising data points, said averaging means holding the first data point and multiplying it by each successive data point so that the frequency spectrum is repeatedly calculated and averaged.
Claim 7
Dependent Claim
23 words
An electrophoretic light scattering apparatus in accordance with claim 1 including electrophoretic cell means comprising a single non-interrupted chamber for holding said solution.
Claim 8
Dependent Claim
41 words
An electrophoretic light scattering apparatus in accordance with claim 8 wherein said means for generating said electric field includes a pair of electrodes, said electrodes being positioned at opposite ends of said chamber to establish said electric field across said solution.
Claim 9
Dependent Claim
54 words
An electrophoretic light scattering apparatus in accordance with claim 9 wherein said electrophoretic cell means includes light conducting means positioned adjacent to said cell and between said electrodes, said light conducting means conducting said light beam from said laser means to enter said chamber means incident to the direction in which said macromolecules flow.
Claim 10
Dependent Claim
26 words
An electrophoretic light scattering apparatus in accordance with claim 10 wherein said light conducting means is positioned normal to the direction in which said macromolecules flow.
Claim 11
Dependent Claim
28 words
An electrophoretic light scattering apparatus in accordance with claim 1 wherein said laser means includes an Ar laser emitting an incident light beam on the 5145 Angstrom line.
Claim 12
Dependent Claim
125 words
An electrophoretic light scattering apparatus for determining the electrophoretic mobility and diffusion coefficient of a macromolecular polymer in solution, said apparatus comprising in combination: means for establishing an electric field across said solution to move said macromolecules through said solution at a velocity proportional to said electrophoretic mobility in a direction parallel with said electric field; laser means for generating a light beam of monochromatic electromagnetic radiation incident on said macromolecules, said light beam being scattered by said macromolecules to provide a frequency distribution representative of said diffusion coefficient and a Doppler shift proportional to said electrophoretic mobility of said macromolecular polymer; and detector means for analyzing said scattered light to determine said electrophoretic mobility and said diffusion coefficient of said macromolecular polymer in solution.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-10-15 | 1977-04-16 | 1977-10-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-15 | 1981-04-16 | 1981-10-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-15 | 1985-04-16 | 1985-10-16 | $7700.00 | Window Closed / Lapsed |