Xác định hàm lượng Betamethason trong thuốc mỡ bôi da bằng phương pháp sắc kí lỏng hiệu năng cao (HPLC)

A simple, rapid, accurate and sensitive method was developed for qualitative and quantitative analysis of Betamethason dipropionat in ointment using high performance liquid chromatography (HPLC) with UV detection. Experimental results optimize the chromatographic conditions with a flow rate of 1.5ml.min-1 thus reducing the running time of the samples, the chromatograms obtained meet the symmetry coefficient. At the same time, optimizing the processing of samples with a high fat sample should combine ultrasound and cooling, as the recovery efficiency increased significantly from 62,27% to 99.66% with relative standard deviation %RSD=0.96 (<2.00 %). Chromatography parameters were stainless steel RP-18 column (250mm x4.6mm i.d., 5μm particle size), at 40oC. The isocratic mobile phase was methanolbuffer solution at pH=7.0 (7030; v/v). The determinations were performed using UV-Vis detector set at 240nm. Samples were prepared with ethanol and the volume injected was 20μl. The analytical curve was linear (r2=0.9991) with the concentration range of 4.01- 16.05μg.ml-1. The presence of components of the ointment did not interfere with the results of the analysis. The method showed adequate precision, with a relative standard deviation (%RSD) lower than 2.00%. The correctness of the method is in the range of 99.05÷100.91% with %RSD=0.77.