IADR Abstract Archives
Synthesis of methacrylated chitosan biopolymers for use in tissue engineered scaffolds
Objectives: Chitosan-based biomaterials have garnered great attention for use in bone regeneration. Yet, their use has been limited by insufficient efforts to develop these materials for micro-patterning. In this study, 3D printing was used to micro-pattern chitosan hydrogels into 3D structures for applications in bone regeneration. Thus, we test the hypothesis that 3D printed chitosan hydrogels have sufficient strength and stability to be used in applications of bone healing.
Methods: Methacrylated chitosan (MaCH) was synthesized by mixing acetic acid, deionized water, chitosan, methacrylate anhydride, pyridine, and various ethanol concentrations (25-50 mL). Ethanol was added to open chitosan chains, exposing more amino groups to methacrylate anhydride. The degree of methacrylation determines solubility in water. After synthesis, the solution was dialyzed against ultrapure water (18.2 Ω). After purification, one group of each ethanol concentration was freeze-dried for a week. Sucrose was dissolved (1:1 mole) in the other group, then freeze-dried. Methacrylation was tested by FTIR. Each group was tested for solubility. 4 wt.% MACh from each group was prepared for 3D printing, and IRGACURE 2959 was used for crosslinking. During printing, crosslinking was initiated by UV light (365nm, 42 mW.cm-2) at the tip of the printer nozzle.
Results: FTIR confirmed successful methacrylate grafting into chitosan backbone. The 45ml ethanol concentration resulted in the greatest dissolution, indirectly indicating the highest degree of methacrylation. Addition of sucrose to dialyzed MACh considerably increased its solubility. This may be attributed to the sucrose interaction with chitosan (making them globular) and preventing water from aligning the chitosan chain parallel and packed. 4 wt. % MACh was printed successfully with good integrity of micropatterns.
Conclusions: Methacrylated chitosan has the potential to be 3D printed and micropatterned. These properties can be used for the application of tissue regeneration.
Methods: Methacrylated chitosan (MaCH) was synthesized by mixing acetic acid, deionized water, chitosan, methacrylate anhydride, pyridine, and various ethanol concentrations (25-50 mL). Ethanol was added to open chitosan chains, exposing more amino groups to methacrylate anhydride. The degree of methacrylation determines solubility in water. After synthesis, the solution was dialyzed against ultrapure water (18.2 Ω). After purification, one group of each ethanol concentration was freeze-dried for a week. Sucrose was dissolved (1:1 mole) in the other group, then freeze-dried. Methacrylation was tested by FTIR. Each group was tested for solubility. 4 wt.% MACh from each group was prepared for 3D printing, and IRGACURE 2959 was used for crosslinking. During printing, crosslinking was initiated by UV light (365nm, 42 mW.cm-2) at the tip of the printer nozzle.
Results: FTIR confirmed successful methacrylate grafting into chitosan backbone. The 45ml ethanol concentration resulted in the greatest dissolution, indirectly indicating the highest degree of methacrylation. Addition of sucrose to dialyzed MACh considerably increased its solubility. This may be attributed to the sucrose interaction with chitosan (making them globular) and preventing water from aligning the chitosan chain parallel and packed. 4 wt. % MACh was printed successfully with good integrity of micropatterns.
Conclusions: Methacrylated chitosan has the potential to be 3D printed and micropatterned. These properties can be used for the application of tissue regeneration.