A modified experimental setup for sedimentation equilibrium experiments with gels. Part 2: Technical developments

Area of Science:

• Biophysical Chemistry
• Materials Science
• Analytical Chemistry

Background:

• Analytical ultracentrifugation (AUC) is a powerful technique for characterizing macromolecules and their interactions.
• Investigating gels and solutions requires efficient experimental setups capable of handling multiple samples under identical conditions.
• Previous methods limited the number of simultaneous measurements, hindering comprehensive analysis.

Purpose of the Study:

• To describe technical developments for an efficient experimental setup for gel investigation using equilibrium analytical ultracentrifugation (eAUC).
• To present new cell centerpieces and optical system modifications for enhanced sample analysis.
• To enable accurate and simultaneous measurement of a large number of samples for comprehensive system characterization.

Main Methods:

• Development of new 10-channel centerpieces for Schlieren optics.
• Implementation of a programmable multiplexer and a modified Schlieren optical system.
• Introduction of new centerpieces for Rayleigh interference and UV-absorption optics, supporting 10, 12, or 26 samples.
• Discussion of material selection for cell centerpieces and windows for adhering samples (gelatin/water system).
• Presentation of a phase volume calculation for circular sample channels to correct for broadened menisci.
• Integration with an 8-hole rotor for simultaneous measurement of up to 70 samples.

Main Results:

• New centerpieces and optical modifications facilitate efficient eAUC experiments.
• The developed system allows for the investigation of up to 70 samples simultaneously.
• Material compatibility for adhering samples, such as gelatin/water, is addressed.
• Phase volume calculations provide accurate corrections for broadened menisci.
• The enhanced throughput allows for comprehensive characterization of gel/solvent systems under identical conditions.

Conclusions:

• The described technical developments significantly improve the efficiency and capability of equilibrium analytical ultracentrifugation for investigating gels and solutions.
• The ability to measure numerous samples simultaneously provides unprecedented возможности for detailed system characterization.
• These advancements are applicable to both gel and solution studies, broadening the utility of the technique.