3D printing, an additive manufacturing based technology for precise 3D construction, is currently widely employed to enhance applicability and function of cell laden scaffolds. Research on novel compatible biomaterials for bioprinting exhibiting fast crosslinking properties is an essential prerequisite toward advancing 3D printing applications in tissue engineering. Printability to improve fabrication process and cell encapsulation are two of the main factors to be considered in development of 3D bioprinting. Other important factors include but are not limited to printing fidelity, stability, crosslinking time, biocompatibility, cell encapsulation and proliferation, shear-thinning properties, and mechanical properties such as mechanical strength and elasticity. In this review, we recite recent promising advances in bioink development as well as bioprinting methods. Also, an effort has been made to include studies with diverse types of crosslinking methods such as photo, chemical and ultraviolet (UV). We also propose the challenges and future outlook of 3D bioprinting application in medical sciences and discuss the high performance bioinks.

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A strategy utilizing elastin peptide macroporous cryogels to build highly flexible scaffolds to load carbon nanotubes, polypyrrole, and iron oxide magnetic nanoparticles, is presented. This combines high elasticity, flexibility, shape memory property, and injectable property together with conductivity and/or magnetic responsive property. The network can afford 97.5% compressive strain with an excellent conductivity of 50.1 ± 2.9 S cm(-1) at 90% strain.

Strong, stretchable, and durable biomaterials with shape memory properties can be useful in different biomedical devices, tissue engineering, and soft robotics. However, it is challenging to combine these features. Semi‐crystalline polyvinyl alcohol (PVA) has been used to make hydrogels by conventional methods such as freeze–thaw and chemical crosslinking, but it is formidable to produce strong materials with adjustable properties. Herein, a method to induce crystallinity and produce physically crosslinked PVA hydrogels via applying high‐concentration sodium hydroxide into dense PVA polymer is introduced. Such a strategy enables the production of physically crosslinked PVA biomaterial with high mechanical properties, low water content, resistance to injury, and shape memory properties. It is also found that the developed PVA hydrogel can recover 90% of plastic deformation due to extension upon supplying water, providing a strong contraction force sufficiently to lift objects 1100 times more than their weight. Cytocompatibility, antifouling property, hemocompatibility, and biocompatibility are also demonstrated in vitro and in vivo. The fabrication methods of PVA‐based catheters, injectable electronics, and microfluidic devices are demonstrated. This gelation approach enables both layer‐by‐layer and 3D printing fabrications.