The resolution of 3-hydroxy butiric acid's rasemic mixture by the chiral pirkle type chromatography

In this study, Pirkle type chiral stationary phases (Csp) was prepared and resolution studies of racemic 3-hydroxybutyric acid were made. When a new chiral stationary phase (CSP) is prepared, Sepharose-4B was used as a matrix. L-Tyrosine as an spacer-arm was attached to the matrix, N-p-aminobenzyl-(R)-2-amino-1-buthanol was connected as ligand to this spacer-arm via diazo. Then racemic mixture of 3-hydroxybutyric acid was loaded to the column. By using buffer solutions as moving phase at different pH?s ( pH = 6,7,8), the resolution was supplied. The flow rate of eluat was adjusted with peristaltic pump. The total 12 tubes eluat were took. Absorbance values of the tubes were read at 330 nm with spectrophotometer. In the 6th,7th and 8th tubes the material (3-hydroxybutyric acid) was determined. The studies were repeated at pH 7 and pH 8. But, A result wasn?t achieve. After rotation angle of 6th, 7th and 8th tubes were determined at pH 6, the enantiomeric excess was found as 11.4