Phosphoramide Hydrogels\nas Biodegradable Matrices\nfor Inkjet Printing and Their Nano-Hydroxyapatite Composites

Inkjet printing is a leading technology in the biofabrication\nof\nthree-dimensional biomaterials, offering digital, noncontact deposition\nwith micron-level precision. Among these materials, hydroxyapatite\nis widely recognized for its use in bone tissue engineering. However,\nmost hydroxyapatite-laden inks are unsuitable for inkjet printing.\nTo address this, we developed photocurable and biodegradable phosphoramide-based\nhydrogels containing thiol-functionalized polyethylene glycol via\nclick chemistry. These hydrogels degrade into phosphates, the natural\ncomponent of bone. The rheological properties of the inks are finely\ntuned through chemical design to meet the requirements of nanohydroxyapatite\ncomposite inks for piezoelectric inkjet printing. We demonstrated\ntheir printability using simple geometric patterns, showcasing a versatile\nand efficient solution for the precise inkjet printing of biomaterial\ncomposites.