Layer-by-layer assembly: A versatile approach for tailored biomedical films and drug delivery

Layer-by-layer (LbL) assembly has revolutionized the field of biomedical engineering by enabling the precise design and fabrication of thin multilayer films with diverse functionalities. This article provides a comprehensive review of the applications of LbL assembly in drug delivery, antimicrobial action, wound healing, and tissue engineering. The LbL technique involves the sequential adsorption of oppositely charged materials onto a substrate, facilitating the incorporation of different chemical species through electrostatic interactions and other driving forces. This approach offers remarkable control over film properties such as porosity, mass, and thickness, and provides the flexibility to incorporate multiple components within the film structure. In drug delivery applications, LbL-produced films have demonstrated exceptional potential for controlled and sustained release of therapeutic agents, minimizing dosing frequency and improving patient compliance. Studies successfully report incorporated antimicrobials, anticancer agents and growth factors into LbL assemblies, demonstrating their effectiveness in targeted drug delivery and combating microbial infections. In addition, LBL assembly has emerged as a promising approach for wound healing strategies. By incorporating bioactive molecules and growth factors, these films promote tissue regeneration, angiogenesis and accelerated wound closure, thereby improving the overall wound healing process. In the field of tissue engineering, LbL-produced films provide a versatile platform for constructing bioactive structures that mimic the extracellular matrix and support cell attachment, proliferation, and differentiation. This versatile approach has significant implications for the development of tissue substitutes and regenerative therapies. This review also emphasizes the influence of LbL assembly methods on film properties, including thickness and porosity, and highlights the effect of various parameters such as pH, solvent, ionic strength, and temperature on film formation.