How are 3D cultures made?

3D cultures are artificially created environments that enable biological cells to grow or interact with their surrounding extracellular framework in three dimensions. There are a number of ways 3D cell cultures can be made. Generally, they can be classified in 2 types of 3D culturing methods: scaffold technique and the scaffold-free technique. The scaffold techniques include the use of solid scaffolds, hydrogels and other materials which allow growth in all directions. Scaffold-free techniques include the use of low adhesion plates, hanging drop plates, micropatterned surfaces, and rotating bioreactors, magnetic levitation, and magnetic 3D bioprinting. This method relies on cells to self-assemble into clusters or spheroids.