Shannon sampling based approach for the structural solution of nano-objects by laboratory and synchrotron SAXS data

Area of Science:

• Materials Science
• Biophysics
• Physical Chemistry

Background:

• Small-angle X-ray scattering (SAXS) is crucial for characterizing nanoscale structures.
• Traditional SAXS analysis often relies on the pair distance distribution function P(r) or model-dependent fitting.
• These methods can be computationally intensive and may require specific structural models.

Purpose of the Study:

• To introduce a novel Shannon sampling-based approach for SAXS data analysis.
• To bypass the need for calculating the P(r) function and model-dependent fitting.
• To enable direct determination of structural parameters from SAXS data.

Main Methods:

• Utilized Shannon sampling principles for direct analysis of SAXS data in the q-domain.
• Applied the method to both laboratory and synchrotron SAXS datasets.
• Tested on various systems including micelles and proteins (lysozyme, apoferritin, carbonic anhydrase 2).

Main Results:

• Successfully derived key structural parameters without P(r) or model fitting.
• Demonstrated reliability even with laboratory data and polydisperse samples.
• Accurately determined parameters like maximum size, mass, volume, asymmetry, hydration, and core-shell properties.

Conclusions:

• The Shannon sampling approach offers a robust and efficient alternative for SAXS data analysis.
• It provides direct access to essential structural information, simplifying characterization.
• The method is versatile, applicable to diverse samples and scattering conditions.