Triple detection GPC/SEC is a well-established method for the accurate and complete characterization of macromolecules. The technique combines both light scattering and viscometer detectors with a refractive index (RI) detector and is applicable to both natural molecules, such as proteins or polysaccharides, and synthetic polymers.
The resulting data on structure and molecular weight can prove useful for scientists studying macromolecules. This white paper describes the hypothesis behind the advanced detector technology and provides a better understanding of its strengths and drawbacks.
The following sections are covered in the white paper, describing the principles of triple detection GPC/SEC:
- 1. The RI Detector
- 1.1 Theory
- 1.2 Chromatographic Method
- 1.3 Are Other Concentration Detectors Suitable for Triple Detection?
- 2. The Low Angle Light Scattering Detector
- 2.1 Theory
- 2.2 Elution Profiles
- 2.3 Determination of Instrument Constants (Calibration)
- 2.4 Molecular Weight Distribution
- 3. The Viscometer Detector
- 3.1 The Differential Viscometer Design
- 3.2 The differential Viscometer Theory
- 3.3 Viscosity Functions
- 3.4 Applications – Universal Calibration
- 3.5 Applications – Measurement of Hydrodynamic Radius, Rh
- 3.6 Applications – Measurement of Polymer Structure and branching
Summary
In this white paper, we have seen how triple detection combines measurements from multiple detectors to offer not only increased amounts of data, but also information, which is available thanks to the combination of different detectors and would not be obtainable using the individual detectors separately.
The light scattering detector provides complete information about molecular weight, regardless of column calibration standards, and the RI detector is capable of determining a precise concentration profile.
The viscometer offers critical structural information, making it possible to use GPC/SEC to establish these parameters as hydrodynamic size variations in proteins or branching in polymers. Measurement of these parameters is now made easy with a single detector or a combination of two detectors. The complementary data rendered by all three detectors reinforces the power of triple detection.
This information has been sourced, reviewed and adapted from materials provided by Malvern Panalytical.
For more information on this source, please visit Malvern Panalytical.