Advantages and Prospective Implications of Smart Materials in Tissue Engineering: Piezoelectric, Shape Memory, and Hydrogels

Abstract

Conventional biomaterial is frequently used in the biomedical sector for various therapies, imaging, treatment, and theranostic functions. However, their properties are fixed to meet certain applications. Smart materials respond in a controllable and reversible way, modifying some of their properties because of external stimuli. However, protein-based smart materials allow modular protein domains with different functionalities and responsive behaviours to be easily combined. Wherein, these "smart" behaviours can be tuned by amino acid identity and sequence. This review aims to give an insight into the design of smart materials, mainly protein-based piezoelectric materials, shape-memory materials, and hydrogels, as well as highlight the current progress and challenges of protein-based smart materials in tissue engineering. These materials have demonstrated outstanding regeneration of neural, skin, cartilage, bone, and cardiac tissues with great stimuli-responsive properties, biocompatibility, biodegradability, and biofunctionality.

Keywords: piezoelectric material; polymeric hydrogels; shape-memory material; smart material; stimuli-responsive material; tissue engineering.

Figure 1

Schematic illustration of how proteins can be bioengineered to be used as smart materials for tissue engineering (Adapted with permission from [9] copyright 2020 Elsevier. Ltd.).

Figure 2

PLMC composite scaffold SME on filling bone screw hole (modified from [92] and created using Adobe Illustrator).

Figure 3

Preparation of pH-sensitive SMP with SME (created using Adobe Illustrator).

Figure 4

Self-healing hydrogels process happening in circular hydrogels which has been cut into several pieces (created using Adobe Illustrator).