OPEN ACCESS Eurasian Journal of Analytical Chemistry ISSN: 1306-3057 2017 12(6):953-962 DOI: 10.12973/ejac.2017.00224a © Authors. Terms and conditions of Creative Commons Attribution 4.0 International (CC BY 4.0) apply. Correspondence: Ebru Çubuk-Demiralay, Department of Chemistry, Faculty of Science and Literature, Süleyman Demirel University, 32260 Isparta, Turkey. Tel: +90 246 2114167, Fax: +90 246 2371106. ebrucubukdemiralay@gmail.com Simultaneous Quantitative Determination of Imidazole Antimycotics in Human Urine by using RPLC Technique Zehra Üstün Süleyman Demirel University, TURKEY Ebru Çubuk-Demiralay Süleyman Demirel University, TURKEY Received 13 April 2017 ▪ Revised 5 August 2017 ▪ Accepted 7 August 2017 ABSTRACT Imidazoles are well known heterocyclic compounds having important feature of a variety of medicinal agents. Studies with imidazole containing compounds are great importance in the clinical use of drugs. The presence of imidazole group in the molecules of lanoconazole (LCZ) and butoconazole (BCZ) is very important for its chemical and analytical behavior. Target analytes were efficiently separated with a Pinnacle DB Cyano column (5 µm, 4.6 x 250 mm I.D.) and oxiconazole (OCZ) used as an internal standard. In this study, correlation between the retention factors of the solutes and pH of the mobile phase was determined at ten pH values in acetonitrile-water binary mixture. In optimization condition, quantification of these drugs were performed in human urine. The linear responses were observed over a wide concentration range (6.25.10 -6 -3.13.10 -5 mol L -1 for LCZ and 6.32.10 -6 - 2.53.10 -5 mol L -1 for BCZ) in human urine. The method were validated by determining the limits of detection (LODs, 2.01.10 -6 - 5.50.10 -7 mol L -1 ), the limits of quantification (LOQs, 6.08.10 -6 - 1.67.10 -6 mol L -1 ), recoveries (99.14%, 99.93%) and intra-day and inter-day relative standard deviations (RSDs, <1%). The data presented in this report demonstrate a rapid, sensitive and accurate method for the simultaneous analysis of LCZ and BCZ in human urine for pharmacokinetic studies. Keywords: imidazole antimycotics, RPLC, method validation, human urine INTRODUCTION Antimycotics are a group of pharmaceuticals with increasing consumption rates. Imidazoles constitute the most important class of antimycotic drugs which have broad-spectrum antifungal activities against wide range of fungi that cause many of mycotic infections. This aromatic heterocyclic structure is a “1,3-diazole” and is classified as an alkaloid (Figure 1). Imidiazole ring is amphoteric, because it functions as an acid as well as a base. Basic pKa of imidazole ring is about 6.90. [1].