Chaotropic salts impact in HPLC approaches for simultaneous analysis of hydrophilic and lipophilic drugs.

Shulyak, Nataliia; Piponski, Marjan; Kovalenko, Sergiy; Stoimenova, Tanja Bakovska; Drapak, Iryna; Piponska, Magdalena; Rezk, Mamdouh R; Abbeyquaye, Annie Donkor; Oleshchuk, Oleksandra; Logoyda, Liliya

Simultaneous determination of drugs with different physico-chemical properties necessitates thorough research and careful selection of HPLC conditions. In the present study, various concepts of HPLC method development for this aim are discussed. Moreover, the work was motivated by the advantages of utilizing different chaotropic anions as a new promising approach to overcome the limitations of ion-pairing agents commonly used for this purpose. Based on log P values, atorvastatin (log P = 6.36) and lisinopril (log P = -1.22) were chosen as representative examples for lipophilic and hydrophilic drug, respectively. Several simple, economic, fast and reliable HPLC methods were developed for their simultaneous analysis and are presented in a comparative manner highlighting their advantages and the limitations. Elution profile showed satisfying retentions and resolution about 3. Photo-diode array calculations were exploited for identifying the molecules by their UV spectra and peak purity, calculated and presented as rectangular shaped ratio grams. The linearity check showed excellent results, and satisfactory system suitability parameters of both peaks. This confirms the investigation results and conclusions for the influence of the chaotropic salts on N-containing molecules, by increasing their retentivities, and improving peak shapes, even on different quality columns without end-capping and base-deactivating of separation matrixes. This article is protected by copyright. All rights reserved.