Nanoarchitectonics for Free‐Standing Polyelectrolyte Multilayers Films: Exploring the Flipped Surfaces

Abstract The competency of polyelectrolyte multilayer films (PEM) self‐assembly to modulate the surface architecture at the molecular level has emerged as a captivating technique for various biomedical applications. PEM advancement in bio‐applications covered the development of bio‐sensors, stimuli‐responsive drug‐delivery systems, surface modification for creating antibacterial surfaces, and tissue‐engineering architectures. Different PEM blends, from natural to synthetic ones, have been explored to make a free‐standing version of the PEM stack. This review provides a deeper understanding of the free‐standing PEM (FS‐PEM), their fabrication strategies, and essential properties for specified bio‐applications. The most crucial aspect of fabricating FS‐PEM is choosing an application‐specific fabrication protocol to delaminate the PEM stack from the underlying substrates. Post‐fabrication, there are important considerations to improve the mechanical stability of these FS‐PEMs by crosslinking or adding desired nanoparticles. Overall, essential insights are discussed here for using FS‐PEM for specific bio‐application, which has received little attention in the material science community until now.