(684f) Role of Solvents in Drug Adsorption in Metal Organic Frameworks (MOFs)

Solvent is known to play a critical role in determining the loading of drugs in porous cargos. Molecular simulations can be useful in providing useful insights on different interactions that control this adsorption at the molecular-level. However, most of the existing simulation studies are performed in the absence of solvent thus neglecting their key role in determining drug adsorption in these porous materials. Here, we perform molecular simulations using the following five commonly used solvents for loading of 5-Fluorouracil, Ibuprofen and Hydroxyurea in MOFs: ethanol, acetone, ethyl acetate, acetonitrile, and methanol. Three MOFs, namely, UiO-AZB, HKUST-1 and NH2-MIL-53 with different pore geometries and sizes were selected. The adsorption isotherm suggests that a low pressure (< 10^-9 bar) solvent does not play any role as the adsorption is determined by electrostatic interactions. However, at pressure > 10^-9 bar the adsorption was significantly overestimated in the absence of solvent, showing the importance of solvent in determining the drug adsorption. Radial Distribution Function (RDF) and heat of adsorption analysis were performed to investigate structural and physical-chemical characteristics at molecular level determining the adsorption mechanism in presence and absence of solvent environment.