Biocompatible nanomaterials have attracted enormous interest for biomedical applications. Carbonaceous materials, including carbon nanotubes (CNTs), have been widely explored in wound healing and other applications because of their superior physicochemical and potential biomedical properties to the nanoscale level. CNTs-based hydrogels are widely used for wound-healing and antibacterial applications. CNTs-based materials exhibited improved antimicrobial, antibacterial, adhesive, antioxidants, and mechanical properties, which are beneficial for the wound-healing process. This review concisely discussed the preparation of CNTs-based hydrogels and their antibacterial and wound-healing applications. The conductive potential of CNTs and their derivatives is discussed. It has been observed that the conductivity of CNTs is profoundly affected by their structure, temperature, and functionalization. CNTs properties can be easily modified by surface functionalization. CNTs-based composite hydrogels demonstrated superior antibacterial potential to corresponding pure polymer hydrogels. The accelerated wound healing was observed with CNTs-based hydrogels.

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Cellulose is the most venerable and essential natural polymer on the planet and is drawing greater attention in the form of nanocellulose, considered an innovative and influential material in the biomedical field. Because of its exceptional physicochemical characteristics, biodegradability, biocompatibility, and high mechanical strength, nanocellulose attracts considerable scientific attention. Plants, algae, and microorganisms are some of the familiar sources of nanocellulose and are usually grouped as cellulose nanocrystal (CNC), cellulose nanofibril (CNF), and bacterial nanocellulose (BNC). The current review briefly highlights nanocellulose classification and its attractive properties. Further functionalization or chemical modifications enhance the effectiveness and biodegradability of nanocellulose. Nanocellulose-based composites, printing methods, and their potential applications in the biomedical field have also been introduced herein. Finally, the study is summarized with future prospects and challenges associated with the nanocellulose-based materials to promote studies resolving the current issues related to nanocellulose for tissue engineering applications.

The conversion of liquid resin into solid structures upon exposure to light of a specific wavelength is known as photopolymerization. In recent years, photopolymerization‐based 3D printing has gained enormous attention for constructing complex tissue‐specific constructs. Due to the economic and environmental benefits of the biopolymers employed, photo‐curable 3D printing is considered an alternative method for replacing damaged tissues. However, the lack of suitable bio‐based photopolymers, their characterization, effective crosslinking strategies, and optimal printing conditions are hindering the extensive application of 3D printed materials in the global market. This review highlights the present status of various photopolymers, their synthesis, and their optimization parameters for biomedical applications. Moreover, a glimpse of various photopolymerization techniques currently employed for 3D printing is also discussed. Furthermore, various naturally derived nanomaterials reinforced polymerization and their influence on printability and shape fidelity are also reviewed. Finally, the ultimate use of those photopolymerized hydrogel scaffolds in tissue engineering is also discussed. Taken together, it is believed that photopolymerized 3D printing has a great future, whereas conventional 3D printing requires considerable sophistication, and this review can provide readers with a comprehensive approach to developing light‐mediated 3D printing for tissue‐engineering applications.

One of the significant challenges in bone tissue engineering (BTE) is the healing of traumatic tissue defects owing to the recruitment of local infection and delayed angiogenesis. Herein, a 3D printable multi‐functional hydrogel composing polyphenolic carbon quantum dots (CQDs, 100 µg mL−1) and gelatin methacryloyl (GelMA, 12 wt%) is reported for robust angiogenesis, bone regeneration and anti‐tumor therapy. The CQDs are synthesized from a plant‐inspired bioactive molecule, 1, 3, 5‐trihydroxybenzene. The 3D printed GelMA‐CQDs hydrogels display typical shear‐thinning behavior with excellent printability. The fabricated hydrogel displayed M2 polarization of macrophage (Raw 264.7) cells via enhancing anti‐inflammatory genes (e.g., IL‐4 and IL10), and induced angiogenesis and osteogenesis of human bone mesenchymal stem cells (hBMSCs). The bioprinted hBMSCs are able to produce vessel‐like structures after 14 d of incubation. Furthermore, the 3D printed hydrogel scaffolds also show remarkable near infra‐red (NIR) responsive properties under 808 nm NIR light (1.0 W cm−2) irradiation with controlled release of antitumor drugs (≈49%) at pH 6.5, and thereby killing the osteosarcoma cells. Therefore, it is anticipated that the tissue regeneration and healing ability with therapeutic potential of the GelMA‐CQDs scaffolds may provide a promising alternative for traumatic tissue regeneration via augmenting angiogenesis and accelerated immunomodulation.