On-column approach in the HPLC-UV analysis of non-chromophoric compounds using azelaic acid as a model

The manuscript introduces a detection solution of compounds lacking chromophoric properties [e.g. azelaic acid] by implementing a HPLC-UV analysis with on-column derivatisation of the analyte. Azelaic acid was used to test the feasibility of the method at Lamda [max] = 265 nm. Its chromatographic analysis shows linear [R = 0.999], precise [RSD < 2.0%] and accurate [97.0 - 103.5%] behavior. Furthermore, the method was found selective for azelaic acid in a prepared cream which contains other ingredients such as triethanolamine, vaseline and stearic acid. The limit of detection [LOD] and limit of quantification [LOQ] of azelaic acid were 9 and 30 micro g/ml, respectively