The Recipes for Different 3D Printing Bio-Ink

3D bioprinting is one of the cutting-edge technologies in recent years, by using computer programming, difficult geometry can be printed. For the 3D printing skin, it just this kind of feature to do the complex mission. One domination issue of the 3D bioprinting skin is the printing material, Bio-Ink. Nowadays, there are five typical materials for Bio-ink, separate into two different categories, three are NATURAL Bio-Ink and two are SYNTHETIC Bio-Ink, analyzation on performance, application and advantages have been done on these materials. In recent years, a different kind of Bio-Ink has been invented, the Complex Bio-Ink, which uses two or more kinds of materials to improve the performance and cover the disadvantages that the other materials meet. This review summarizes the commonly used printing materials, including performance, production and application. Also to improve them, a new kind of Bio-Ink, complex Bio-ink is introduced. By analyzing the improvements of the Complex one compared with the traditional one, a future imagination for 3D Bio-Ink based on the definition of Complex Bio-Ink has been raised.