Greenness assessment of two chromatographic methods developed for the determination of Mupirocin in two binary mixtures along with its impurity.

Two simple, accurate and precise chromatographic methods have been developed and validated for estimating Mupirocin (MUP) in two binary mixtures. Mixture (1); with Fluticasone propionate (FLU) together with two of their impurities, namely; Pseudomonic acid-D (Pseud-D) and Fluticasone impurity C (FIC). Mixture (2); with Mometasone furoate (MF) along with Pseud-D impurity. High performance thin layer chromatography (HPTLC-densitometry) and high performance liquid chromatography (RP-HPLC) were the two proposed methods. In the HPTLC method, good separation of both mixtures was achieved by using HPTLC plates pre-coated with silica gel 60 F as stationary phase and the mobile phase consisted of toluene: chloroform: ethanol at a ratio of (5: 4: 2, by volume). The detection was carried out at 220 nm for MUP and 254 nm for FLU, MF, Pseud-D and FIC. In the HPLC method, chromatographic separation was carried out using Agilent Eclipse XDB (250 mm×4.6 mm, 5 μm) C18 column. For mixture (1), a mobile phase of methanol: sodium di-hydrogen phosphate (pH 3.0) was applied in stepwise gradient elution starting at ratios of (50: 50, v/v) and then switching to (80: 20, v/v) after 7 min at a flow rate of 1 mL.min. Detection was performed using diode array detector at 220 nm for MUP and Pseud-D and 240 nm for FLU and FIC. For mixture (2), the same mobile phase was used, but in isocratic elution in the ratio (80: 20, v/v) at flow rate of 1 mL.min and detection at 220 nm for MUP and Pseud-D and 248 nm for MF. The two methods successfully separated the cited drugs and were used to determine the drugs in pure form as well as pharmaceutical dosage forms. Validation was done as per International Council on Harmonization guidelines. Furthermore, the greenness of the proposed methods compared to the reported method, was evaluated as per the National Environmental Method Index, analytical Eco scale, Green Analytical Procedure Index and Analytical Greenness metric approaches.