The problem of treating chronic wounds is widespread throughout the world and carries a huge cost. Biomaterials engineering tries to solve this problem by creating innovative bioactive dressings dedicated to specific types of wounds. Both synthetic and natural polymers are the main base to produce wound dressings. Biopolymers have the advantage over synthetic polymers by being more biocompatible, non-toxic, biodegradable, and eco-friendly. The aim of this work was to produce a bioactive biomaterial based on natural polymers with potential applications to manage chronic highly exuding and infected wounds. A newly developed method for chemical synthesis of the curdlan/agarose biomaterial at high temperature combined with freeze-drying process resulted in a superabsorbent dressing material with antibiotic immobilized. The obtained biomaterial was subjected to basic microbiological in vitro tests and a cytotoxicity assay according to ISO 10993-5. Moreover, the experimental treatment of the infected wound in a veterinary patient was performed using the developed material. Based on the conducted research, it was proved that the produced dressing is not toxic to normal human skin fibroblasts. An additional advantage of the biomaterial is its ability to inhibit the growth of harmful microorganisms, such as Staphylococcus aureus and Pseudomonas aeruginosa. Furthermore, the experimental treatment confirmed the validity of using the produced biomaterial as a dressing dedicated to the treatment of difficult-to-heal infected wounds. To summarize, the produced biomaterial possesses great potential to be used as a wound dressing for infected wounds.