Abstract: The validity of the modified free volume diffusion model proposed in the previous paper ( I ) was tested for the interpretation and correlation of data on diffusion in polyacrylamide gel and immobilized yeast cell matrix. The effects of monomer concentration, crosslinking degree, temperature, diffusant size and cell loadings on the effective diffusivities of the diffusants in the above media were quantitatively correlated and qualitatively explained quite well with the model. Good agreement between the regressed equation predictions and the experimental data was obtained. Some semi- empirical equations were also obtained to relate the effective diffusivity in the gel to the composition of the initial solution.