# Droplet Ripening in Concentration Gradients

## TL;DR

This paper presents a theoretical analysis of droplet behavior in concentration gradients, revealing how droplets drift, grow, and segregate, with implications for cellular organization and phase separation.

## Contribution

It introduces a new growth law for droplets in gradient systems and explains their drift, growth, and segregation dynamics, including transient arrest phenomena.

## Key findings

- Droplets exhibit drift velocity and position-dependent growth.
- The dissolution boundary moves, segregating droplets.
- Steep gradients cause transient arrest of droplet growth.

## Abstract

Living cells use phase separation and concentration gradients to organize chemical compartments in space. Here, we present a theoretical study of droplet dynamics in gradient systems. We derive the corresponding growth law of droplets and find that droplets exhibit a drift velocity and position dependent growth. As a consequence, the dissolution boundary moves through the system, thereby segregating droplets to one end. We show that for steep enough gradients, the ripening leads to a transient arrest of droplet growth that is induced by an narrowing of the droplet size distribution.