Impurity Profiling and Identification of 2,6-Diisopropylphenol by HPLC Method and Raman Spectroscopy Method

Identification of 2,6-diisopropylphenol by Raman spectroscopy using the TruScan Raman spectrum is validated by specificity test and robustness. HPLC assay method is developed to detect the 2,6-diisopropylphenol and its impurities A = determination of 2,6-diisopropylphenol; its main impurities related compound A = 2,6-diisopropylphenyl isopropyl ether, related compound B = 2,6-diisopropylquinone, and related compound C = 3,3'-5,5'-tetraisopropyl diphenol; and unknown impurities done by HPLC method. Related compound A and C determination has been developed by normal phase HPLC; good resolution peak shapes have resulted from the peak results. The limit of impurities A and C is reported to be 0.05% and 0.03%, and the limit of impurity B is also detected by using the same above procedure, but the column has been changed for the maximum wavelength detection and better elution from the peak results. The reported impurity level was 0.02%, the unknown impurity limit was 0.0149%, and the total impurity level of 2,6-diisopropylphenol was reported to be 0.06% which are in the threshold limit level. It specifies that the drug is safe and efficient without any toxicity.