Enhancement of Cooling Rate Using Biodegradable MgO Nanoparticles During a Cryopreservation Process

摘要

Cryopreservation is the method of the preservation of biological tissue samples for future usages without incurring significant changes to functional properties. A two-dimensional numerical model is developed in the current work to study the role played by MgO nanoparticles in enhancing the freezing rate of the tissue during cryopreservation. The Pennes bio-heat model is the governing equation in this case. Finite volume method is employed to discretize the governing equation while the tri-diagonal matrix algorithm is used for solving the discretized algebraic equations for obtaining temperature distribution within the tissue. The movement of solid-liquid interface during freezing is tracked using the enthalpy-porosity method. Validation of this model is first done with the result of the existing literature. Then, the effect of MgO nanoparticles in enhancing the freezing rate is studied by increasing the volume fraction of the nanoparticles in the tissue-nanoparticle system up to 30%. Finally, a comparative study is made to analyse the performances of MgO and Fe_3O_4 nanoparticles in quickening the freezing process during cryopreservation.