3D Bioprinted hydrogels with alkannins/shikonins for wound healing

Skin is the body’s largest organ and serves as a protective barrier against the external environment. While minor wounds can heal naturally, deeper or chronic wounds often require medical treatment to prevent infection and long-term complications. Traditional methods like skin grafting have several limitations, including limited donor site availability and the risk of complications such as infection, inflammation, or donor site damage. Tissue engineering offers a promising alternative by developing scaffolds that support tissue repair, while avoiding common problems associated with conventional treatments [ 1 ] [ 2 ]. In this study, we explored the incorporation of plant-derived natural compounds into 3D-printed hydrogel scaffolds designed for wound healing applications. The composite scaffolds were fabricated using Gelatin Methacrylate (GelMA) and alginate, two soft materials recognized for their biodegradability and biocompatibility [ 3 ]. To enhance the scaffolds′ therapeutic potential, we impregnated them with a mixture of alkannins/shikonins (A/S), bioactive molecules isolated from the roots of Alkanna tinctoria , which comprise the active pharmaceutical ingredients of the strong wound healing ointments HELIXDERM ®​ and Epouloderm ®​ . A/S possess well established antimicrobial, anti-inflammatory, and wound-healing properties [ 4 ]. We compared two methods for incorporating A/S into the scaffold: embedding A/S during hydrogel preparation before 3D printing and immersion after printing. The scaffolds were tested in vitro for their cytocompatibility with fibroblasts, antibacterial activity, and drug release. Preliminary results indicated that the drug loading method influenced the scaffold’s overall performance and bioactivity. While further research is needed, this work highlights how natural compounds can be exploited in new wound healing materials and scaffolds. Publication History Article published online: 05 March 2026 © 2026. Thieme. All rights reserved. Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany