HPLC-UV Determination and Comparison of Extracted Corticosteroids Content with Two Methods

Abstract

Counterfeited topical preparations and their presence on the market are the problems in the whole World. There are a great number of manufacturers who are making and selling preparations as natural and pure herbal in which they add corticosteroids. These corticosteroids are not declared and a consumer doesn’t know that these preparations are counterfeited. The aim of this investigation was to examine the influence of different extraction solvents in the analysis of corticosteroids content. The analysis was performed with HPLC-UV Agilent 1220 with manual injection. The first method used reversed-phase Zorbax Phenyl, 250 × 4.6 mm, 5.0 µm column at a wavelength of 240 nm. Injection volume was 20 µL and the oven temperature was 45 ℃. The mobile phase was water, HCOOH 0.1%:acetonitrile HCOOH 0.1% with a flow rate fixed at 1.0 mL/min. Extraction was done with pure methanol and a mixture of methanol:water = 50:50. Better extraction with pure methanol was for hydrocortisone; while mometasone was better extracted with a mixture of methanol:water = 50:50 and other corticosteroids had pretty much equal results in both solvents. The second method used a ZORBAX Eclipse XDB-C18, 150 × 4.6 mm, 3.5 µm column at 254 nm. Injection volume was 20 µL and the oven temperature was 25 ℃. The mobile phase was acetonitrile:water = 55:45 with a flow rate fixed at 1.0 mL/min. In this work two different methods of extraction were presented and the problems that could appear during the analysis of corticosteroids.