Advancements in hydrogels: A comprehensive review of natural, synthetic, and hybrid innovations for wound healing.

Natural and synthetic hydrogels are beneficial for wound healing because of their biocompatibility, biodegradability, and capability to maintain a moist healing environment. Natural hydrogels, sourced from materials like hyaluronic acid (HA), chitosan, alginate, and collagen, replicate the extracellular matrix and play a vital role in cell migration, proliferation, and tissue regeneration. These materials promote wound healing by keeping a moist environment and offer inherent biological benefits, including anti-inflammatory, antioxidant, and antimicrobial properties. These contribute to accelerated healing and lower infection risk. For instance, chitosan is known for its antimicrobial properties, while HA can enhance tissue hydration and angiogenesis by developing new blood vessels. However, natural hydrogels face challenges like limited mechanical strength, instability, and variable degradation rates. These issues can hinder their long-term effectiveness in wound care applications. Natural hydrogels are often modified through crosslinking or combined with synthetic polymers to address these limitations. Combining both types into composite hydrogels offers a promising solution. Natural polymers enhance biological functions, while synthetic polymers improve mechanical strength. These hybrid hydrogels can also be loaded with bioactive agents like growth factors or stem cells to boost further healing. This combination addresses the limitations of each type, making composite hydrogels an ideal choice for wound dressings, specifically for chronic wounds and burns. Through merging the biological benefits of natural hydrogels with the customizable properties of synthetic ones, composite materials offer greater tissue regeneration, lowered healing time, and better clinical effects in wound care.