Molecular Dynamics Study of Self-Assembly of Low Molecular Mass Organic Gelators

Molecular Dynamics Study of self-assembly of Low Molecular Mass Organic Gelators

Md Masrul Huda and Neeraj Rai

Dave C. Swalm School of Chemical Engineering, and Center for Advanced Vehicular Systems, Mississippi State University, Miss. State, MS, USA

            Molecular gels are formed by supramolecular assembly of low molecular-mass organic gelators (LMOG) in organic solvents. These molecular gels find numerous application including drug delivery, scaffold for tissue engineering, environmental remediation, etc. Despite significant advances made in the field, our understanding of how gelator molecules lead to complex self-assembled fibrillar network (SAFIN) is rather poor. Here, we present molecular dynamics simulation results that provide insights in the early stage assembly of self-assembled fibrillar network (SAFIN) of selected LMOGs in organic solvents. This molecular dynamics study consists of atomistic simulation, coarse graining simulation, and steered molecular dynamics (SMD) to investigate different stages of evolution of SAFIN.  Atomistic force field has been used to reveal initial growth of aggregates of LMOG molecules while we have used coarse-grained representation for solvent molecules to study the larger systems. Furthermore, we employ steered molecular dynamics to access long time scale inaccessible by traditional molecular dynamics techniques. To validate our approach in molecular gel system, sol/gel transition temperature has been calculated by measuring specific volume of gel at different temperatures. The calculated gelation temperatures are in excellent agreement with the experiments.