# Recent Developments in Materials Science for the Conservation and Restoration of Historic Artifacts
## 5 Biopolymers: Sustainable Conservation Solutions
### Potential Applications of Biopolymers  
Biopolymers have a wide range of potential applications in conservation, including their use as coatings, adhesives, and antimicrobial treatments. Their use as coating materials is based on several properties of biopolymers, which makes them suitable in heritage science:  
* Protective barriers: biopolymer coatings can serve as protective barriers against environmental factors such as moisture, dust, and pollutants. For example, chitosan-based coatings have been shown to effectively protect outdoor stone sculptures from biodegradation [85]. These coatings not only protect but also maintain the aesthetic qualities of artifacts.
* Surface modification: the application of biopolymer coatings can modify surface properties to enhance durability and resistance to wear. These coatings can also improve aesthetic qualities by providing a uniform finish [86]. The ability to customize surface properties is crucial for preserving the visual integrity of cultural heritage items.
* Reversibility: many biopolymer coatings are designed to be reversible, allowing conservators to remove or adjust treatments without damaging the underlying material [87]. This property is particularly valuable in conservation practices where preservation integrity is paramount. Reversible coatings ensure that future interventions can be made without compromising previous work.  
Another potential application is represented by the use of biopolymers as adhesives, which leads to the development of formulations with special properties:  
* Biopolymer-based adhesives exhibit strong bonding capabilities while remaining compatible with various substrates. For instance, gelatin-based adhesives have been widely used in paper conservation due to their excellent adhesion properties [88]. The versatility of biopolymer adhesives makes them suitable for different types of materials.
* The use of non-toxic biopolymer adhesives minimizes health risks for conservators and ensures that treated artifacts remain safe for display or handling [89]. This aspect is increasingly important as awareness grows regarding the hazards associated with synthetic adhesives.
* Biopolymer adhesives can be applied using various methods--such as brushing, spraying, or dipping--allowing for flexibility in application depending on the artifact's needs [90]. The adaptability of these adhesives enhances their usability across diverse restoration projects.  
Finally, the biopolymer can represent a viable alternative in antimicrobial treatments, replacing potential hazardous chemicals:  
* Certain biopolymers possess inherent antimicrobial properties that make them effective against bacteria, fungi, and other microorganisms that may threaten cultural artifacts. For example, chitosan has demonstrated significant antimicrobial activity against a range of pathogens [91]. This property is particularly beneficial in preventing biological deterioration.
* The application of antimicrobial biopolymer treatments can help prevent biological deterioration in artifacts made from organic materials such as wood or textiles. By inhibiting microbial growth, these treatments extend the lifespan of conserved items [85]. Antimicrobial treatments are essential for maintaining artifact integrity over time.