A Comprehensive Brownian Dynamics-Based Forward Model for Analytical (Ultra)Centrifugation

作者：Thajudeen Thaseem^*; Walter Johannes; Uttinger Maximilian; Peukert Wolfgang^*

来源：Particle & Particle Systems Characterization, 2017, 34(1): 1600229.

DOI：10.1002/ppsc.201600229

• analytical ultracentrifugation
• Brownian dynamics
• extinction coefficient
• Mie scattering
• multiwavelength detectors

In this study, it is demonstrated how Brownian dynamics (BD) simulations can be used as a comprehensive forward model for analytical ultracentrifugation (AUC) and analytical centrifugation experiments. BD simulations are a versatile alternative to the numerical solution of Lamm's equation. Time dependent concentration profiles can be accurately predicted by means of the BD simulations even for colloidal systems with multiple species. It is shown that in combination with Mie's theory for light scattering, BD simulations can be extended to generate data mimicking a multiwavelength detector for AUC. The forward model can be utilized as a comprehensive tool for developing and testing sophisticated data analyzing tools that can enhance the capabilities of using centrifugation-based techniques for characterizing nanoparticles. The model is validated using common analysis tools developed for the evaluation of sedimentation velocity data generated by a single wavelength extinction detector. The accuracy of the code is also proved using the recently developed and highly versatile High Dynamic Range-MULTIwavelength FITting tool for accurately predicting particle size distributions via gravitational sweep experiments performed in AUCs equipped with multiwavelength detectors.

• 出版日期2017-1