ABSTRACT
I. Introduction .................................................................................................................... 125
II. Solid-Liquid Phase Separation ..................................................................................... 126
A. Preparation of Polymer Matrices ........................................................................... 126
III. Liquid-Liquid Phase Separation ................................................................................... 128
A. Preparation of Continuous Network Polymer Matrices ........................................ 129
B. Preparation of Polymer Matrices with a Nano-Fibrous Network ......................... 130
C. Preparation of Polymer Matrices with Platelet-Like Structures ........................... 131
D. Preparation of Nano-Fibrous Matrices with Macroporous Structures .................. 132
1. Creating Macroporous Structures with Salt or Sugar Particles ...................... 132
2. Creating Macroporous Structures with Sugar Fibers ..................................... 132
3. Creating Macroporous Structures with Paraffin Microspheres ...................... 133
4. Creating Macroporous Structures with Solid Freeform Fabrication .............. 135
IV. Conclusions .................................................................................................................... 135
References ................................................................................................................................... 136
Synthetic biodegradable polymers such as poly(L-lactic acid) (PLLA), poly(glycolic acid) (PGA),
and poly(D,L-lactic-co-glycolic acid) (PLGA) have been widely used as scaffolding materials in
tissue engineering. Because these materials are biocompatible, degradable by hydrolysis, and are
among the few synthetic polymers approved by the Food and Drug Administration (FDA) for
certain clinical applications, these polyesters remain popular for use as scaffolding polymers. When
preparing these polymers for scaffolding purposes, it is important that the scaffold perform a
number of critical functions. The scaffold should have an open porous structure for uniform cell
seeding and for mass transport of nutrients and metabolic waste removal, it should have a suitable
surface for cell attachment, proliferation, and differentiation, and it should provide a three-
dimensional template that guides tissue growth.
