Information gain from isotopic contrast variation in neutron reflectometry on protein-membrane complex structures

Area of Science:

• Materials Science
• Biophysics
• Crystallography

Background:

• Neutron and X-ray reflectometry are crucial for characterizing surface architectures.
• Designing experiments requires understanding how scattering contrast influences information gain.

Purpose of the Study:

• To develop a framework for quantifying information gain in reflectometry experiments.
• To investigate the impact of scattering contrast on experimental design for biological and soft-matter systems.

Main Methods:

• Applied a framework to quantify information gain from virtual neutron and X-ray reflectometry experiments.
• Implemented marginalization of information gain with respect to structural model parameters.
• Simulated surface architectures of increasing complexity, from simple models to protein-lipid membrane complexes.

Main Results:

• Information gain is primarily determined by the local scattering contrast between a feature of interest and its molecular environment.
• The signal-to-noise ratio of measured reflectivity globally modulates information gain.
• Experimental design should prioritize optimizing local scattering contrast.

Conclusions:

• Local scattering contrast is the dominant factor for maximizing information gain in reflectometry.
• Experimental design should focus on enhancing the contrast of regions of interest.
• Signal-to-noise ratio is a secondary but important factor for global information gain.