3D Printing Smart Hydrogels And Its Application In Drug Delivery

Ordinary hydrogels are mostly single polymers with single functions,which greatly limit the application of hydrogels.Smart hydrogels,also called multifunctional hydrogels,have a wide range of applications in the biomedical field.However,it is relatively difficult to make smart hydrogels with specific external shapes and internal structures,which limits the application of smart hydrogels.3D printing technology,a3D model manufacturing technology which controlled by computer,uses a 3D printer to print materials layer by layer according to the 3D model.The 3D printing technology can not only customize the external shape of the hydrogels,but also design the internal structure of the hydrogels.This study provides a 3D printing method for making smart hydrogels and for drug delivery.The specific research content is as follows:1.3D printing shape memory hydrogels and its application in drug deliveryHydrogels with shape memory behavior and internal structure have wide applications in fields ranging from tissue engineering and medical instruments to drug delivery;however,creating the hydrogels has proven to be extremely challenging.This study presents a Three-Dimensional?3D?printing technology to fabricate the shape memory hydrogels with internal structure?SMHs?by combining sodium alginate and pluronic F127 diacrylate macromer?F127DA?.SMHs were constituted by a double network structure.One is a stable network which formed by F127DA photo-crosslinking;the other one is a reversible network which formed by Ca²⁺cross-linked alginate.SMHs recovery ratio was 98.15%in 10 min,and the elastic modulus keep essentially stable after the shape memory cycle.It showed drug releasing rate was rapider compared with traditional drug-loaded hydrogels in vitro experiments.The viability of 3T3 fibroblasts remained intact which revealed its excellent biocompatibility.Therefore,SMHs have a huge application prospective in drug carriers and tissue engineering scaffold.2.3D printing self-driven hydrogels and its application in drug deliverySelf-driven hydrogels with customizable shapes have wide applications in fields ranging from drivers and medical devices to drug delivery;however,creating the hydrogels has proven to be extremely challenging.Based on the previous studies,this study presents a 3D printing technology to fabricate the double-layer self-driven hydrogels by use sodium alginate and F127DA.The F127DA hydrogels formed by photo-crosslinking which swell in acidic solution;the alginate hydrogels formed by calcium ions cross-linking which does not swell in acidic solution.Different swelling properties cause different internal stresses of the hydrogel,which driving the hydrogels to deform.Within 10 min,there was a significant driving deformation.The drug loading of different hydrogels layers showed different drug release properties.3T3 fibroblasts had a high survival rate which showed its excellent biocompatibility.Therefore,3D printing self-driven hydrogels have a great application prospects in drug carriers and tissue engineering scaffolds.