Synthesis of stimuli-responsive inks for 3D printing of biodegradable structures

The field of 3D bioprinting has gained a lot of interest in recent years due to the growing demand for synthetic replacement of organs and tissues. The technology of 3D printing makes it possible to create customizable implants with high resolution and tunable properties, allowing for better compatibility to the patient and the specific medical need. A crucial step in the design process of such structures is selecting a biocompatible ink that holds the desired mechanical properties.

Our research focuses on designing biodegradable inks, targeted to be used for the printing of rapid-degrading hydrogel platforms intended for the insertion of cells and tissues into the body. The hydrogel inks are PEG based and are crosslinked under UV radiation. The crosslinked hydrogels contain degradable bonds that undergo hydrolysis in presence of enzymes that are naturally present in the body, causing the gel to degrade to its initial components that can be later cleared from the body. The ink system contains many variables such as polymer chain length, concentration, reagents ratio and type of solvent, which in turn allows for a broad spectrum of hydrogels with different properties to be achieved. Using these inks we have printed various structures with microscale features that have tunable degradation rates ranging from hours to a few days.