Bio-engineering thermodynamics: an engineering science for thermodynamics of biosystems

Abstract

Cells are open complex thermodynamic systems. Energy transformations, thermo-electro-chemical processes and transports occur across the cells membranes. Different thermo-electro-biochemical behaviours occur between health and disease states. Moreover, living systems waste heat, the result of the internal irreversibility. This heat is dissipated into the environment. But, this wasted heat represent a sort of information, which outflows from the cell toward its environment, completely accessible to any observer. Consequently, the analysis of irreversibility related to this wasted heat can represents a new approach to study the behaviour of the cells. So, this approach allows us to consider the living systems as black boxes and analyze only the inflows and outflows and their changes in relation to the modification of the environment. Therefore, information on the systems can be obtained by analyzing the changes in the cell heat wasted in relation to external perturbations. In this paper, a review of the recent results obtained by using this approach is proposed in order to highlight its thermodynamic fundamental: it could be the beginning of a new engineering science, the bioengineering thermodynamics. Some experimental evidences from literature are summarized and discussed. The approach proposed can allow us to explain them.

Keywords

• Entropy generation; Exergy; Irreversibility; Living systems; Medicine and biochemistry thermodynamics; Membrane transport