Study On Quality Standards Of Pantethine And Diacerein

Study on quality standards of pantethine and diacerein Speciality Pharmaceutical Analysis Graduate Student Xue-fan CHEN Supervisor Su ZENGStudy on the Pantethine StandardPantethine is a part of coenzyme A,a very important substance that participates in the metabolism of carbohydrates,amino acids,fatty acids and dozens of other important chemical reactions.Some researchs indicate that pantethine may help lower cholesterol and other lipid levels,improve fatty liver,enhance cognitive abilities,increase energy levels. No significant side effects have been reported for pantothenic acid or pantethine,used by themselves or with other medications.As noted above,pantethine has been used in people with diabetes,without apparent adverse effects.However,maximum safe dosages for young children,pregnant or nursing women,or people with serious liver or kidney disease have not been established.In this study,pantethine was identified specifically by using thin layer chromatography(TLC) and chemical reaction.The related substance was detected by using high performance liquid chromatography(HPLC) and TLC.Both methods could detect the acid,the alkali and the oxidative degradation product effectively.The TLC method could detect the light degradation product keenly compared to the HPLC method.The HPLC detection wavelength was set at ultraviolet termination,so there was a high level of baseline noise that did not favor for analyzing the related impurities.Therefore,the TLC method was used to detect the related substances.A gas chromatography(GC) method was established to determine the organic solvents including methanol,chloroform and pyridine in pantethine.The limit of detection(LOD) was 0.02μg·mL^-1,0.99μg·mL^-1,0.49μg·ml^-1,respectively.The HPLC method and the titrimetric method were used to assay the content.The titrimetric method was consistent with the HPLC method for determination of pantethine content.The titrimetric method is convenient,accurate,easy operation,so it was used as standard method for assaying the pantethine.The established standard could be used for the quality control of pantethine.Study on the Diaeerein StandardDiacerein was the most important inhibitor of the interleukin.In clinic,it was mainly used for treating the osteoarthritis and rheumatism arthritis.The studies have demonstrated that diacerein can delay the course,reduce the ache,and improve patient's quality of life,because it might obviously improve the osteoarthritis patient's joint function.In this study,diacerein was identified specifically by using the retention time of HPLC, infrared spectrophotometric method and chemical method.The related substance and the content were determined by using HPLC method.An Agilent Zorbax C₁₈(250×4.6mm,5μm ) was employed as analytical column,the mobile phase consisted of water(adjust pH to 2.5 by glacial acetic acid)-methanol- acetonitrile(40:45:15 ),the detection wavelength was set at 254 nm and the flow rate of mobile phase was 1.0ml min^-1.Standard curve was linear over the concentration range of 4.28～51.38μg g·ml^-1 with correlation coefficient 0.9999.The average recovery was 99.1%(RSD=0.76%,n=9).The organic solvents in diacerein were detected by using GC method.The five residual volatile organic solvents and internal standard,tetrahydrofuran,were separated completely.The resolution and sensitivity were acceptable.The limits of detection was 1.35μg·mL^-1 for methanol,0.80μg·mL^-1 for toluene, 1.12μg·mL^-1 for ethanol,0.67μg·mL^-1 for acetone,4.19μg·mL(-1) for dimethylacetamide.The established standard could be used for the quality control ofdiacerein.