Enantioselective Separation and Detection of D-Phenylalanine Based on Newly Developed Chiral Ionic Liquid Immobilized Silica Gel Surface

This study introduced a simple method developed for enantioselective extraction of D-phenylalanine prior to its determination by high performance liquid chromatography. The method was based on silica gel developed by surface immobilized new chiral ionic liquid (SG-L-PhAlaC2NTf2). Surface characteristics of the synthesized SG-L-PhAlaC2NTf2 phase were confirmed by both FT-IR spectroscopy and scanning electron microscope. Results of the selectivity study and effect of pH on SG-L-PhAlaC2NTf2 phase showed that SG-L-PhAlaC2NTf2 was the most enantioselective toward D- phenylalanine. Data of adsorption isotherm study revealed that the adsorption capacity of SG-L- PhAlaC2NTf2 for D-phenylalanine was the most by 97.35% as compared to activated silica gel at pH value of 3.0 and after one hour contact time. Results demonstrated that the adsorption of D- phenylalanine onto SG-L-PhAlaC2NTf2 phase well followed with Langmuir adsorption isotherm and pseudo second-order kinetic models. The efficiency of the methodology was ultimately validated by implementing it to real water samples with satisfactory results.