Objective:To investigate the effect of vacant capsules made from hydroxypropyl starch on the content of spironolac-tone. Methods:The spironolactone capsules were placed under the conditions with (4 000 ± 500) lx, 40℃ and RH (75 ± 5) % for 5 days and 10 days, respectively. An HPLC method was used to analyze the content of spironolactone, and the changes in appearance, color and the other traits were also observed. Results:The content of spironolactone was within the range of 93. 45%-100. 37% after the above tests, which was conformed to the standard(93. 0%-107. 0%). Conclusion:The vacant capsules made from hydroxypropyl starch rival have good compatibility with spironolactone.

Objective To establish a capillary gas chromatography( GC)method for the determination of residual organic solvents in poly( lactic-co-glycolide)( PLGA),including methanol,acetone,dichloromethane,and toluene. Methods A capillary GC method was carried out. DB-624 capillary column(30 m× 0. 32 mm,1. 80 μm)with programmed temperature chromatography was employed. The initial temperature was kept at 40 ℃ for 8 min. Then the temperature was raised to 200 ℃ at a rate of 10 ℃·min-1 . The injection port temperature was 180 ℃,and the split ratio was 10:1. The carrier gas was nitrogen. The temperature of FID was set at 250 ℃,and the sample volume was set at 3 μL. Results Four residual organic solvents consisting of methanol,acetone,dichloromethane and toluene in PLGA were completely separated. The linear range of concentration of methanol,acetone,dichloromethane and toluene was within 10. 0-50. 0( r=0. 999 8 ),16. 7-83. 3( r=0.9998),2.0-10.0(r=0.9993),and3.0-14.8(r=0.9997)μg·mL-1,respectively.Therecoveryofmethanol,acetone, dichloromethane and toluene was 99. 9%( RSD=1. 5%),100. 8%( RSD=0. 9%),100. 1%( RSD=1. 1%),and 99. 5%(RSD=0. 6%),respectively. Six batches of samples met the requirements. Conclusion The method is proven to be sensitive and accurate after the validation. It is suitable for the determination of residual organic solvents in PLGA.