| Objective:1.The in vitro release and transdermal permeation behavior of compound clotrimazole cream were studied by flow cell method and diffusion cell method respectively,and the differences in in vitro release and transdermal absorption between compound clotrimazole cream from different manufacturers and imported reference preparation clotrimazole cream were investigated.2.The related quality characteristics of compound clotrimazole cream,such as p H,viscosity,particle size,related substances,cold and heat resistance,were studied,and the determination method of related substances was established and the impurity spectrum was analyzed to ensure the quality controllability and provide reference for the improvement of domestic compound preparation process.3.The stability and biosafety tests were carried out to investigate the changes of compound clotrimazole cream in properties,content,impurities and biosafety.Methods:1.HPLC method was used to establish the content determination method of compound clotrimazole cream and methodological verification;flow-through cell method was used to investigate the difference in the release rate of the imported preparation and the domestic compound preparation at different positions in flow-through cell release media and flow rate,and to determine the optimal conditions for the release of the compound clotrimazole cream;3.Using pig ear skin as transdermal material and30%ethanol-normal saline as receiving medium,the intradermal retention and transdermal amount of reference and domestic preparations were investigated by Franz diffusion cell method.4.The related substances of compound clotrimazole cream were studied by HPLC,and the related impurities were further determined and confirmed by high resolution liquid chromatography-mass spectrometry,and the impurity structure and formation path were analyzed;5.The p H value,viscosity,particle size,cold and heat resistance of the cream were measured by p H meter,viscometer,microscope and particle size analyzer respectively,and the related q-uality characteristics of the cream were investigated;6.Under the temperature of 30°C and relative humidity of 65%,the three-month accelerated stability test of the cream was carried out to investigate the changes of properties,clotrim-azole content and related substances although time;Then,according to the"Technical Guidelines for the Study of Irritation,Allergy and Hemolysis of Chemical Drugs",the irritation test and allergy test were carried out using rabbits and guinea pigs respectively.Results:1.The content of imported and domestic preparations ranged from 98.62%to100.26%;the 24 h cumulative release of cream in semi-solid adapter,glass beads and cotton was 40.9%,71.71%and 89.22%,respectively.With 1%SDS phosphate buffer solution as the release medium,the 24 h cumulative release rate of 4 batches of creams ranged from 77.79%to 98.66%,while the highest in 1%CTAB-PBS and 1%Tween-PBS were 28.65%and 55.42%,respectively.In the three media,the release of domestic preparation and reference preparation was different.The cumulative release rates were 97.81%and 90.34%at the flow rates of 16 and 8 m L·min-1,respectively.3.Using the diffusion cell method,30%ethanol-saline as the receiving medium to investigate the transdermal absorption of the cream,the ratios of the transdermal amount of the three batches of domestic creams and imported creams were:1.32,1.75,1.62,and the ratios of intradermal retention were:1.19,1.57,1.32,the ratio of the amount of intradermal retention to the total amount of transdermal absorption of the four batches of creams was 88.03%～90.19%,and the amount of intradermal retention was much higher than the amount of penetration,which was in line with the clinical medication characteristics of the drug,but the average particle size of the domestic preparation was much larger than that of the imported preparation.4.Based on the chromatographic method of European Pharmacopoeia,a chromatographic method for the determination of related substances in compound clotrimazole cream was established,and the degradation impurities A,D,process impurities B,E,F and their formation mechanism were determined.5.Imported and manufacturer 2 cream p H within a reasonable range,manufacturer 1 and manufacturer 3 cream p H>8.3,prone to the risk of skin irritation;the viscosity of manufacturer 3 is high,and it is not easy to coat and clean;the particle size of creams from different manufacturers was determined by laser particle size analyzer,and the size was as follows:d1（15.5μm）>d3（10.3μm）>d2（7.7μm）>d import（4.7μm）.Manufacturer 3 produced stratification at 50°C.6.In the stability study,with the accelerated test,the color of the imported cream was still white,and the color of the creams of the three domestic manufacturers changed from white to yellowish.The content of clotrimazole in domestic manufacturer 2 cream increased,and the other three manufacturers did not change.The maximum increase of degradation impurity A was only 0.08%after 3 months,and the increase of total impurities was0.04%～0.31%.In the irritation test,there was no erythema and redness in the skin of rabbits in the experimental group.In the allergic test,the sensitization rate of the positive control group was 80%,and the guinea pig skin of the negative control group and the test group did not appear erythema and edema,and did not produce allergy.Conclusion:In this paper,the in vitro release and transdermal absorption characteristics of the cream were investigated by flow cell method and Franz diffusion cell method,respectively,combined with factors such as particle size and excipients in the prescription.Combined with the characteristics of particle size and excipients in the prescription,the original clotrimazole cream was used as a reference to provide reference for semi-solid quality evaluation,and to provide reference for the development of other compound preparations and the optimization of prescription process.The proposed new chromatographic method for the related substances of compound clotrimazole cream can accurately and effectively detect the impurities related to clotrimazole,and provide data support for the impurity research and quality evaluation of this variety.In the study of other quality characteristics,the p H of two domestic creams was higher,the viscosity of one domestic cream was higher,the particle size of all domestic creams was larger than that of imported creams,and one domestic cream was not heat-resistant,suggesting that there was a gap between this product and the imported reference cream,and there was still room for improvement.The stability test showed that the compound clotrimazole cream was stable,but the related enterprises should pay attention to the sealing of packaging materials to avoid the risk of drug quality.The biosafety test showed that compound clotrimazole cream had no irritation and sensitization. |
