Recent advancements in extrudable gel-based bioinks for biomedical settings

Biomaterials have been used since ancient times to stimulate non-functional or injured tissues and organs. Metals were the very first materials utilized for this function, and as time progressed, innovative materials such as ceramics, polymeric, and nanocomposite were brought to the area used in clinical applications. Over the last century, developments in material sciences, cell biology, technology, and engineering enabled 3D printing of live tissues or organ models in the desired shape and geometry utilizing cells alone or in combination with hydrogels via additive manufacturing. This review aims to provide a brief overview of the features and qualities of bioink materials, as well as their applications in the cardiac sector and skin regeneration. As a result, inkjet 3D printing and laser-assisted 3D printing are extensively used. Bioink formulations based on diverse biomaterials are described, and combined bioink methods are further addressed. Scaffold-based bioink is the most common type, in which cells are covered with hydrogels or other foreign materials before being bioprinted into 3D structures. A different kind of scaffold-free bioink material has also been utilized. Furthermore, many applications using 3D bioprinting are outlined, including heart patches, tissue-engineered cardiac muscle, wound dressing, wound healing, and cancer therapy.