Formation of a 3-D Network in Alginate Spheres

FORMATION OF A 3-D NETWORK IN ALGINATE SPHERES

 

West Virginia University, Department of Chemical Engineering

Paula Pacurari, Dr. Robin Hissam

 

A current challenge in the study of cancer is the development of 3D models for cell growth.  Growth of cells on flat surfaces may not allow for proper signaling or migration, yielding results that may not mimic the actual behavior of cancer cells in vivo.  With a focus on leukemia, a material that will mimic the bone marrow microenvironment can serve as a new model for the study of leukemic stem  cells. Alginate is an immunocompatible biopolymer that is capable of immobilizing viable cells and bioactive factors and is a common biological material used in drug delivery and biomaterial applications. Upon the addition of CaCl_2, alginate forms a hydrogel which can be modified into different 3-D structures.  The bone marrow microenvironment is highly porous, and this project was to develop alginate structures that mimic the bone marrow microenvironment and can be used as a 3-D model.  Alginate beads were formed using different solution concentrations to create materials of varying microstructures.  Swelling ratio tests were performed to determine the porosity and diffusion rate of fluid into the material.  In addition, the morphology of the beads was characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were be used to characterize the structure of the 3-D networks. The bead structures were also compared to a bulk gel structure, which indicates the production of beads results in more porosity on the surface.