Lignin and Its Composites for Tissue Engineering

Abstract

Tissue engineering (TE) is a progressive field that aims to provide alternative treatments that bypass drawbacks of conventional medicine. The components of a tissue-engineered construct include commonly a scaffold and cells with or without biochemical molecules. The interactions between these components and the surrounding target tissue determine the success of the construct. Therefore, certain criteria must be met in scaffolds designed for clinical purposes. In this chapter, these criteria will be introduced. Focus is given to lignin, the second most abundant biopolymer on earth. Its availability, biocompatibility, antioxidant and antimicrobial activities, biodegradability, and mechanical properties have attracted the attention of researchers in many applications including biomedical applications. Recent efforts focus on the utilization of lignin as a sustainable building unit for the preparation of scaffold materials. In this chapter, the properties of lignin that contribute to its bioactivity, especially its antioxidant and antimicrobial properties, will be discussed. The benefits of using lignin compared to other materials will be highlighted, followed by addressing the criteria that should be met when designing a lignin-based scaffold. Also, possible cellular compositions of several targeted tissues will be introduced in the context of their natural characteristics within the respective tissue. Another focus will be the possible utilization of various stem cells and their secreted biomolecules for their feasibility as cell sources for scaffolds to be intended for TE. Understanding these tightly orchestrated systems provides an insight into suitable cellular models for testing newly fabricated scaffolds for future applications in clinical settings.