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Abstract The mechanism of separation methods, for example, liquid chromatography, is realized through rapid multiple adsorption‐desorption steps leading to the dynamic equilibrium state in a mixture of molecules with different partition coefficients. Sorting of colloidal particles, including protein complexes, cells, and viruses, is limited due to a high energy barrier, up to millions kT, required to detach particles from the interface, which is in dramatic contrast to a few kT for small molecules. Such a strong interaction renders particle adsorption quasi‐irreversible. The dynamic adsorption‐desorption equilibrium is approached very slowly, if ever attainable. This limitation is alleviated with a local oscillating repulsive mechanical force generated at the microstructured stimuli‐responsive polymer interface to switch between adsorption and mechanical‐force‐facilitated desorption of the particles. Such a dynamic regime enables the separation of colloidal mixtures based on the particle‐polymer interface affinity, and it could find use in research, diagnostics, and industrial‐scale label‐free sorting of highly asymmetric mixtures of colloids and cells. 

Abstract The mechanism of separation methods, for example, liquid chromatography, is realized through rapid multiple adsorption‐desorption steps leading to the dynamic equilibrium state in a mixture of molecules with different partition coefficients. Sorting of colloidal particles, including protein complexes, cells, and viruses, is limited due to a high energy barrier, up to millions kT, required to detach particles from the interface, which is in dramatic contrast to a few kT for small molecules. Such a strong interaction renders particle adsorption quasi‐irreversible. The dynamic adsorption‐desorption equilibrium is approached very slowly, if ever attainable. This limitation is alleviated with a local oscillating repulsive mechanical force generated at the microstructured stimuli‐responsive polymer interface to switch between adsorption and mechanical‐force‐facilitated desorption of the particles. Such a dynamic regime enables the separation of colloidal mixtures based on the particle‐polymer interface affinity, and it could find use in research, diagnostics, and industrial‐scale label‐free sorting of highly asymmetric mixtures of colloids and cells. 

Abstract The advancement of new‐generation complex integrated responsive systems depends on the progress in the development of functional stimuli‐responsive polymer components that could be put together and engineered to perform in concert as an ensemble. This progress report highlights recent substantial progress in the development of such soft‐matter components capable of changes according to preprogrammed scenarios. The components interact via interfaces that play a key role in the performance of the microstructured materials. The list of the most important properties that can be changed by altering the interfaces upon external stimuli includes gating, transport, release, wetting, adhesion, and self‐regeneration (healing) realized in different architectures of soft stimuli‐responsive materials.