Synthesis and characterization of the chiral stationary phase based on chitosan

Chitosan was modified with N‐nicotinoyl‐L‐phenylalanine and 3,5‐dimethylphenylisocyanate to prepare a chiral stationary phase for the high performance liquid chromatography application, especially for the separation of optical isomers of series of α‐amino acids. The modified chitosan with N‐nicotinoyl‐L‐phenylalanine group and 3,5‐dimethylphenylcarbamate group was characterized with several analytical methods such as differential scanning calorimeter, thermo gravimetric analyzer, X‐ray diffractometer, and HPLC; its solubility, thermal property, and chiral separation performance were studied. Contrary to chitosan, the modified chitosan prepared in this study showed good solubility in several organic solvents and was easy to handle to coat the silica particles to prepare chiral HPLC column. It showed good chiral separation capabilities. It was also thermally stable at over 100°C, suggesting potential wide operating temperature range of its chiral HPLC column.