Templating Aggregation

TL;DR

This paper introduces a novel templating aggregation process where clusters assemble on scaffolds to react, revealing unique kinetics and extending to more complex reaction schemes, with potential implications for understanding aggregation phenomena.

Contribution

It presents the first analysis of templating aggregation, demonstrating its unusual kinetics and exploring three extensions including multistage reactions and templated ligation.

Findings

Cluster and monomer densities decay as t^{-2/3} in templating aggregation.

Contrasts with conventional aggregation where densities decay as t^{-1}.

Extensions include multistage reactions and templated ligation with diverse scaffold roles.

Abstract

We introduce an aggregation process based on \emph{templating}, where a specified number of constituent clusters must assemble on a larger aggregate, which serves as a scaffold, for a reaction to occur. A simple example is a dimer scaffold, upon which two monomers meet and create another dimer, while dimers and larger aggregates undergo in irreversible aggregation with mass-independent rates. In the mean-field approximation, templating aggregation has unusual kinetics in which the cluster and monomer densities, $c(t)$ and $m(t)$ respectively, decay with time as $c\sim m^2\sim t^{-2/3}$. These starkly contrast to the corresponding behaviors in conventional aggregation, $c\sim \sqrt{m}\sim t^{-1}$. We then treat three natural extensions of templating: (a) the reaction in which $L$ monomers meet and react on an $L$-mer scaffold to create two $L$-mers, (b) multistage scaffold reactions, and (c) templated ligation, in which clusters of all masses serve as scaffolds and binary aggregation is absent.