Geometrical frustration yields fiber formation in self-assembly

Area of Science:

• Biophysics
• Materials Science
• Chemical Engineering

Background:

• Self-assembly of supramolecular structures is crucial for cellular functions and nano/micro-engineering.
• Protein aggregation into fibers occurs in various medical conditions, highlighting a need to understand generic assembly mechanisms.
• Existing research often focuses on specific molecular mechanisms, leaving generic principles of fiber formation less explored.

Purpose of the Study:

• To propose and investigate a minimal model for generic fiber formation from irregular particles.
• To demonstrate that well-defined morphologies, specifically fibers, can arise from particles lacking optimized shapes.
• To elucidate the role of geometrical frustration in the self-assembly of such structures.

Main Methods:

• Development of a minimal computational model simulating the aggregation of ill-fitting, sticky particles.
• Exploration of fiber formation across a range of particle shapes and aggregation conditions.
• Analysis of the influence of geometrical frustration on the assembly process and resulting morphologies.

Main Results:

• Robust fiber formation was demonstrated for various irregular particle shapes and aggregation parameters.
• The minimal model successfully predicted fiber formation, validating the generic mechanism.
• Geometrical frustration was identified as a key factor governing the conditions and stability of fiber formation.

Conclusions:

• Fibers can generically arise from the aggregation of irregular particles with short-range interactions, irrespective of optimized shapes.
• Geometrical frustration is a critical determinant in the self-assembly of these structures, influencing their formation and metastable nature.
• The findings offer a simplified yet powerful framework for understanding fiber formation in both biological and engineered systems.