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

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.

Automated summary

The self-assembly technique of polyelectrolyte multilayer films (PEM) has the potential to modulate the surface architecture for biomedical applications. This review delves into the fabrication strategies and essential properties of free-standing PEM (FS-PEM), as well as provides crucial insights for specific bio-applications using FS-PEM.