本发明公开了一种用于3D打印的浆料、3D结构体及其制备方法和应用，涉及三维生物打印技术领域。用于3D打印的浆料包括海藻酸盐、聚赖氨酸和水，其中海藻酸盐的质量是水质量的20‑40％，海藻酸盐的羧基和聚赖氨酸的氨基的摩尔比为1:0.1‑2。本发明3D结构体的制备方法使用用于3D打印的浆料进行3D打印得到。本发明浆料成型性好，可直接打印出在生理环境下能较为稳定存在的结构体，同时改善了海藻酸盐的生物惰性，通过控制海藻酸钠和聚赖氨酸的比例能够调控支架的整体电荷，利于搭载不同类型的有效生物成分，促进细胞的粘附和增殖。经打印后的结构体经过进一步化学交联稳定性更好，能长时间保持其完整性。

The invention discloses slurry for 3D printing, a 3D structure as well as a preparation method and application thereof, and relates to the technical field of three-dimensional biological printing. Theslurry for 3D printing comprises alginate, polylysine and water, wherein the mass of alginate is 20-40% of the mass of water, and the molar ratio of carboxyl groups of alginate to amino groups of polylysine is 1:(0.1-2). The preparation method of the 3D structure provided by the invention comprises performing 3D printing using the slurry for 3D printing to obtain the 3D structure. The slurry provided by the invention has good formability, can be used for directly printing out a structure which can stably exist under a physiological environment, improves biological inertness of alginate at thesame time, can regulate and control the overall charge of a bracket by controlling the proportion of sodium alginate and polylysine, and is favorable for carrying different types of effective biological components to promote cell adhesion and proliferation. A printed structure has better stability after further chemical crosslinking and can maintain its integrity for a long time.