Silymarin-Functionalized Chitosan–Hydroxyapatite Nanocomposite: A Promising Biomaterial for Oral Health
The development of biocompatible and eco-friendly materials is a key focus of modern biomedicine. A recent study by Subramanian et al. (2025) demonstrates how green synthesis methods can be used to produce innovative nanocomposites with remarkable efficacy for oral health.
In this research, silymarin, chitosan, and nanohydroxyapatite (nHAP) were combined into a multifunctional composite material showing impressive antioxidant, antibacterial, and anti-inflammatory properties.
Triple Action for Teeth and Gums
Silymarin, a plant-derived compound extracted from milk thistle (Silybum marianum), is well known for its antioxidant and anti-inflammatory activity. When combined with chitosan, a biocompatible polymer obtained from chitin, and nanocrystalline hydroxyapatite, a material is formed that addresses several key challenges in oral health: it inhibits the growth of Streptococcus mutans and Porphyromonas gingivalis, supports the healing of inflamed tissue, and promotes regeneration of periodontal structures and bone.
Green Synthesis with Biological Stability
The composite was produced via an environmentally friendly green synthesis route. In this process, silymarin served not only as a bioactive compound but also as a reducing and stabilizing agent. The incorporation of chitosan created a polymer matrix that evenly distributed the hydroxyapatite nanoparticles and prevented aggregation – a common limitation of conventional nanoparticles. Characterization by X-ray diffraction (XRD) confirmed the high crystallinity of the material, while FTIR and electron microscopy (SEM/TEM) analyses verified the successful integration of all components.
Excellent Cell Compatibility and Tissue Integration
Biocompatibility and cell migration assays demonstrated outstanding cytocompatibility of the nanocomposite toward human gingival fibroblasts. Moreover, it promoted fibroblast migration – a crucial step in tissue healing. Particularly noteworthy was its enhanced surface hydrophilicity (contact angle 27.6°), which facilitates the attachment of cells and proteins – a key factor for successful tissue integration.
Chitosan as a Key Component
The study used highly deacetylated chitosan (≥ 85 % DDA), known for its excellent biocompatibility and mucoadhesive properties. This form of chitosan enhances retention on mucosal surfaces and increases the local bioavailability of active compounds. For dental applications such as periodontal dressings, regenerative coatings, or bioactive implant surfaces, chitosans with medium molecular weight (100–300 kDa) are particularly suitable, offering an ideal balance of solubility, stability, and bioactivity.
Antioxidant, Antibacterial, and Anti-Inflammatory
The silymarin–chitosan–hydroxyapatite composite exhibited significantly higher radical-scavenging activity than its individual components. In anti-inflammatory tests, it stabilized human erythrocyte membranes by up to 82 %, confirming its strong inflammation-modulating potential. Through the combination of antioxidant, antibacterial, and anti-inflammatory mechanisms, this material helps maintain oral homeostasis while supporting the healing of gingival and bone tissues.
Conclusion
The silymarin-functionalized chitosan–hydroxyapatite nanocomposite represents a major advancement in the development of bioactive dental materials. Its biocompatibility, environmentally friendly synthesis, and multifunctional bioactivity make it a promising candidate for future applications in periodontology, bone regeneration, and oral wound healing.
For industrial implementation, highly deacetylated chitosans with medium molecular weight, such as those available in our HMC+ Chitosan range, are especially suitable. Their solubility and biological performance can be further optimized through targeted modifications – paving the way for innovative and sustainable solutions in dental medicine.
Reference
Subramanian, A. K., Sivamurthy, G., Karapetyan, K. S., AL-Farga, A., Saleh, R., & Shariati, M. A. (2025). Silymarin-functionalized nanohydroxyapatite-chitosan nanocomposite: a promising biomaterial for oral health applications. BMC Oral Health, 25, 1617. https://doi.org/10.1186/s12903-025-06784-8
First published on 30th of October 2025
Revised on 30th of October 2025