Study On Thiamazole Hydrogel Patch

Thiamazole can restrain the synthesization of hypothyroid homone. Many papers have reported that its oral preparation can produce a series of adverse reactions. In this paper, hydrophile hydrogel transdermal patch was perpared. Thiamazole hydrogel patch has a quality study. In this research, methods about release and transdermal patches performance have been established. In vitro, the best concentrations and the best promoter by.experiments of transdermal permeation were selected. The thyroid drug concentration and the serum thiamazole concentration were determinated by HPLC. Thiamazole was inspected three different formulations of the drug in vivo kinetics. The main results are as follows:(1) Thiamazole hydrogel transdermal patch has been selected by L9 (34) orthogonal experiment. Compared with the traditional PSA, they had advantages of better oxygen permeability properties, viscosity moderate, repeatedly exposed posted better performance and good skin compatibility.(2) HPLC method was selected by determination of faceding the goods and related substances, excipients avoiding interference. Meanwhile destructive sample test results confirmed that the conditions of the chromatographic separation of impurities were appropriate. And the peak was high. It was reliable. Thiamazole had 0.020~1.00μg in the scope of a good linear relationship. The solution had high stability. The average recovery rate reached 99.58%. This hydrogel patch contents uniformity and the substance can be controlled within 0.5%.(3) The methods for measuring its in vitro release degree and its in vitro percutaneous permeability of thiamazole have been constructed. In vitro release degree was up to 95%. To evaluate the percutaneous permeability of thiamazole hydrogel transdermal patch in vitro and compare its characteristic with thiamazole ointment. The experiment results showed that the penetration enhancers were found to increase the penetration of thiamazole and azone had the best penetration enhancing effect. The permeation of thiamazole hydrogel transdermal patch containing 2% azone was in accordance with the zero-order kinetic.(4) The methods for measuring serum and hypothyroid concentration of thiamazole have been constructed. Acetonitrile was used to disposal serum. Methanol was used to disposal hypothyroid. Chromatographic separation of thiamazole was performed on a C-18 reversed phase colum using a mixture of mathanol and water(5:95,V/V) as the mobile phade and ultraviolet detection (252 nm). These methods had some advantages such as convenience, speediness and sensitivity. The serum and hypothyroid have good stability and those recoveries were up to 80%. The inter-and intra-day precision and accuracy were all very good.(5) The same dose of the drug under the same conditions, in serum drug concentrations of hydrogel patch rat was the minimum, next ointment group, a maximum of oral group. Hydrogel patch had themaximum drug concentration in the rat thyroid tissue, next ointment a minimum of oral group.