Shape-free theory for the self-assembly kinetics in macromolecular systems

TL;DR

This paper introduces a shape-free theoretical framework for understanding self-assembly kinetics in macromolecular systems, avoiding assumptions about aggregate shapes, and validates it through stochastic simulations, offering a new way to analyze experimental data.

Contribution

It presents a shape-independent rate theory based on microcanonical analysis for self-assembly, applicable to finite-sized macromolecular systems, validated by simulations.

Findings

The model exhibits a first-order phase transition.

The approach relates equilibrium thermodynamics to rate constants.

It enables reconstruction of free-energy profiles from kinetic data.

Abstract

Self-assembly kinetics is usually described by approaches which assume that the shape of the aggregates has a definite form (e.g., spherical, cylindrical, cubic, etc), however that is unlikely to be the case in many finite-sized macromolecular and colloidal systems. Here we consider a simple aggregation model which displays a first-order phase transition in order to illustrate a rate theory based on microcanonical analysis that allows one to obtain a shape-free description of its self-assembly kinetics. Stochastic simulations are performed to validate our approach and demonstrate how the equilibrium thermostatistical properties of the system can be related to the temperature-dependent rate constants. As a model-independent kinetic approach, it may provide experimentalists a reliable method to reconstruct free-energy profiles and microcanonical entropies from kinetic data.