In this study, molecular dynamics simulation has been used to investigate the interactions of both chiral forms of Phenylglycine amino acid (R- and S- isomers) with micropores of ZSM5-zeolite. Calculated results show that Phenylglycine molecules interact with zeolite surface by electrostatic interactions of their positive charged ammonium group and negative charged carboxylic group. This leads to the formation of two hetero hydrogen bonds between amino groups and oxygen of zeolite framework and also one hydrogen bond between the carboxylic groups and the zeolite surface. Further analyses show that S- isomers have stronger interactions with zeolite surface in comparison to R-isomers. So, movement, radius gyration and angle orientation of S-isomers inside nanopores are decreased, while R-isomers interact more strongly to each other. However, both chiral forms have diffusive behavior along the pores with the self diffusion coefficient of about two orders of magnitude less than that in free water.

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