In the present study, we have developed a mathematical model of drug release from a film of highly swellable gelatin based hydrogel mixed with graphene. The model considers the hydrogel volume expansion because of the swelling as well as the non-linear concentration dependence of the diffusion coefficients for the solvent and the drug. An additionl term is considered for the drug diffusion coefficient enabling the model to predict the drug maximum release from the hydrogel. The model parameters are estimated by genetic algorithem and the model resutls are validated using data sets obtained from experiments on Zoledronic acid, the model drug, loaded hydrogel samples made from several weigth ratios of gelatin to graphene crosslinked with different amounts of glutaraldehyde. The model is further developed to mathematically predict the drug conrolled release into in vivo environment and the impact of several factors influencing the release rate into the surrounding environment is investigated.