ABSTRACT
Objective To establish a method for determining the dissolution of isoniazid tablet in vitro and evaluate the dissolution profiles.Methods The paddle method was used for the dissolution test and the rotation rate was set at 50 r/min.The hydrochloric acid solution (pH 1.2),acetate buffer solution (pH 4.5),phosphate buffer solution (pH 6.8) and water (900 mL) were used as the dissolution media.HPLC was used for the determination of dissolution quantity.Results There was a good linear relationship between the quality concentration of i soniazid and peak area in the range of 0.1981-0.9904μg (r =0.9993).The average recovery was 100.2％.Precision,reproducibility,and specificity tests were good.Among the determination of 16 manufactures,the dissolution profiles in water of four manufactures were not similar with Sandoz reference preparation.Conclusion The HPLC method is simple.The accuracy and specificity of determination of isoniazid dissolution are improved.There is significant difference in the dissolution profiles between different manufactures.The method can be used for the determination of dissolution curves for isoniazid tablets.
ABSTRACT
[Objective]To study the effects of fluoride on the degeneration and ossification of the ligamentum flavum(OLF).[Method]Thirty-six SD rats were divided into two groups,the experimental group was feeded with water of 100 ppm fluoride in distill water,and the control group with distill water.At the end of three and six months,the rats were analyzed with BMD,and the serum and illiac bone samples were collected for detecting the contents of Calcium,Phosphorus,Magnesium,Zinc,Cuprum,Ferrum and Fluoride.At last,the whole lumbar spine were taken for X-ray and pathological observation.[Result]The results showed dental fluorosis appeared in all objectives as compared to almost normal in control group.BMD of the lumbar spine was also greatly high in six month experimental group.The X-ray analysis showed that there were OLF(OLF appeared)in four rats in six month experimental group.Pathological observations showed in six month group,the changes of the ligamentum flavum were more severe than that in 3 months,and there was OLF oringnated from the attachments,mainly intramembranous ossification.[Conclusion]High content of fluoride could lead to the degeneration and ossification of the ligamnetum flavum in rat's lumbar spine,and might play some important role in the ossification of the ligamentum flavum.