Molecular Dynamics Study in Diffusion Weighted MRI - A computational model approach

Molecular Dynamics (MD) is extensively used for analyzing the physical movements of atoms and molecules. It gives the dynamic 'evolution' of the system for a fixed period of time. In simulations, GUV (Giant Unilamellar Vesicle) is used as a model of biological cell. The dependence of saturation inside the GUV on size, pore width etc. has been investigated in this work. Fluorescent chemicals are used as probing agents to observe the diffusion in GUV. As a completely different approach, we introduced diffusion weighted (DW) magnetic resonance imaging (MRI) in MD. When a nanopore forms on the membrane of a GUV, molecular diffusion between the intra and extra cellular regions takes place. The type and nature of diffusion were approximated from diffusion coefficient measurement using model MRI sequences and compared with the recognized values. These investigations may contribute to direct estimation of structural and biophysical parameters within cellular domain and help to understand underlying physiology.