Figure 1.

Theoretical framework for systematic modular design of porous architectures. This framework consists of four hierarchically scaled levels of abstraction, allowing for independent variation of parameters that give rise to all possible architectures. The levels are respectively the surface topography of the pores that can be sensed by individual cells, the pore size and shape, the interfacing of multiple pores, and the macroscopic organization/variations of pores within the scaffold. Examples of systematic variation in two dimensions within each level are depicted. Examples of parameters that can be varied are amplitude and frequency of the surface roughness profile, the size and shape of the pore, the size and number of interconnections for each pore, and the direction (radial or linear) and profile (discrete change or graded) of spatial variation (of pore size in the pictorial example).