Chitosan nanoparticles can now be synthesized using a variety of methods, each with its own benefits depending on the desired application. The first recorded synthesis of chitosan nanoparticles was completed in 1974 by Ohya et al. for use in chemotherapy. They utilized glutaraldehyde as a cross-linking agent to stabilize the nanoparticles. Ohya et al. used a technique known as emulsion cross-linking, where the chitosan is dispersed into an oil phase and linked using a water-soluble cross-linker. This method was also successfully used by Yanat et al. to prepare chitosan NPs that could be used in biodegradable packaging . Emulsion cross-linking allows for specific particle sizes with certain surface properties to be obtained. This method represents a significant milestone in the development of nanoparticle synthesis methods and sets the foundation for research on applying these nanoparticles to drug delivery situations. Ionic gelation is another method that is commonly used for synthesizing chitosan nanoparticles, in which there are ionic interactions between chitosan and anionic cross-linkers, including tripolyphosphate (TPP). Due to the amino groups present in chitosan, it has a positive charge, which will interact with the negatively charged ions from the cross-linker, creating NPs. Without the need to use organic solvents, this method is valued for its environmental friendliness and simple methodology.