Development and Validation of the UPLC Method for the Simultaneous Assay of the Compounding Ointment Components

Semi-solid compounding dosage forms always were popular in the treatment of dermatological diseases all over the world. These medicines are often prepared using industrial production ointments. One of them is the tetracycline hydrochloride ointment with the addition of procaine hydrochloride, sulfanilamide, and sulphur for external use. Since the literature data contains a small amount of information on the methods of quantitative analysis of compounding medicines, the aim of our study was the development of the chromatographic method for the ointment components assay. During the research, HPLC method was developed for the simultaneous assay of studied ointment active ingredients. The procedure was tested on the UPLC due to its advantages. Good separation of sulfanilamide (tR = 0.53 min), procaine hydrochloride (tR = 2.76 min) and tetracycline hydrochloride (tR = 6.50 min) was obtained. Total uncertainty value of the method doesn’t exceed its maximum. The study of the method linearity in the concentration range from 2.34 × 10−6 g/ml to 3.00 × 10−4 g/ml for each component showed good results. Parameters of precision and accuracy of the method meet the established criteria. The obtained RSD values were quite low and indicate good reproducibility of the method. Thus the developed method can be used for the ointment analysis and its chemical stability studies.