Transport properties of agarose gel as a material for cell embedding

Gels consist of dimensional polymer network and solvent. According to the network structure, the substances can percolate through gels. Such a property of the gel is important and useful for a bio-interfacial material. Although pioneering works on the transport properties of gel have been made, the details of the mass transport through the gel are still a matter for discussion. In this paper we would like to present a detailed study on the transport properties of agarose gel. The diffusion coefficients of probe molecules in agarose gel are determined by a newly designed apparatus by the time-lag technique. This technique has advantage that one can determine the permeability coefficient independently. We choose three probes having different molecular weights, namely, glucose, vitamin B12, and bovine serum albumin. It is found that the diffusion coefficients of glucose slightly decrease upon increasing the concentration of agarose but a steep decrease of the diffusion coefficient is observed in the case of bovine serum albumin. The results presumably suggest the network structure of against gel is tenuous. A detailed study on the mass transport properties of gel will promote a better understanding of the network structure of the gel. Furthermore, the results gained by such studies will be desirable to design the bio-interfacial materials such as the cell embedding materials.