The interfacial and bulk properties of the aqueous solutions of the long chain imidazolium-based ionic liquid (IL) viz. 1-decyl-3-methylimidazolium tetrafluoro borate [Dmim][BF4] within L-Arginine and L-Tyrosine have been investigated by surface tension, UV–Visible, fluorescence, viscosity, and FTIR spectroscopy. The surface activity of the [Dmim][BF4]-L-Try was more active on the surface than the [Dmim][BF4]-L-Arg. It's noteworthy to notice that the CMC values of [Dmim][BF4] in water and aqueous amino acids obtained by the UV–Vis spectroscopy method are the same as those determined using the surface tension approach. The additions of AAs function to minimize the CMC values of [Dmim][BF4] as well as the interfacial parameters. An IR probe and the v(C-N) region, which is sensitive to the microenvironment, are used to determine the structure and hydrogen-bonding properties of the IL and two amino acids, specifically the L-Arginine and L-Tyrosine binary systems. The excess IR spectra of the v(C-N) region exhibit positive peaks, which show that the mixing process was insufficient and that complexes with hydrogen bonds had formed in the mixes. The findings could be applied in the pharmaceutical industry to stabilize proteins and prevent protein aggregation.