2025 AIChE Annual Meeting

(476g) Imperfect Turing Patterns: Diffusiophoretic Assembly of Hard Spheres Via Reaction-Diffusion Instabilities

Authors

Ankur Gupta - Presenter, Princeton University
Siamak Mirfendereski, University of Nebraska Lincoln
Turing patterns are stationary, wave-like structures that emerge from the nonequilibrium assembly of reactive and diffusive components. While they are foundational in biophysics, their classical formulation relies on a single characteristic length scale that balance reaction and diffusion, making them overly simplistic for describing biological patterns, which often exhibit multi-scale structures, grain-like textures, and inherent imperfections. Here we integrate diffusiophoretically-assisted assembly of finite-sized cells, driven by a background chemical gradient in a Turing pattern, while also incorporating intercellular interactions. This framework introduces key control parameters, such as the Peclet number, cell size distribution, and intercellular interactions, enabling us to reproduce strikingly similar structural features observed in natural patterns, such as those on the Ornate Boxfish. We report imperfections, including spatial variations in pattern thickness, packing limits, and pattern breakups. With its ability to generate complex structures while capturing fundamental aspects of colloidal physics, our model not only deepens our understanding but also opens a new line of inquiry into imperfect Turing patterns that deviate from the classical formulation in significant ways.