ABSTRACT
@#Dabigatran etexilate mesylate(DE)and tadalafil(TD)are BCS class II drugs with poor water solubility. 〓 In this study coamorphization technique was used to improve their solubilities/dissolutions and hence to enhance their oral absorptions. The coamorphous DE-TD were prepared by solvent-evaporation method and characterized by PXRD, DSC, FTIR and TGA. In addition, dissolution behavior and physical stability were also investigated. Only halo pattern and a single Tg of 119 °C was observed on the PXRD and DSC of the co-evaporated product, respectively, indicating the formation of coamorphous DE-TD. FTIR result suggested that a hydrogen bond was probably formed between N-H group of DE and C==O group of TD. In comparison to crystalline counterparts, coamorphous DE-TD showed a significantly improved intrinsic dissolution rate and prolonged supersaturation time in intrinsic dissolution and supersaturation dissolution studies, respectively. No crystallization was observed under affecting factors testing(30 days)as well as long-term and accelerated stability testing(90 days)for the prepared coamorphous DE-TD under 25°C/60%RH or 40°C/75%RH, while amorphous DE crystalized at 10 days under 25 ℃/75% RH.
ABSTRACT
AIM: To compare the dissolution of asperosaponin Ⅵ between the ultra-micro powder and the fine powder of Radix Dipsaci.METHODS : The real contents,in vitro release and releasing rate of asperosaponin Ⅵ were determined by HPLC for the ultra-micro powder and the fine powder.RESULTS: In the ultra- micro powder and the ordinary powder,the real content of asperosaponin Ⅵ were 4.87%,4.74%,respectively; in vitro release in 1 h were 48.2 mg/g,47.5 mg/g,respectively; releasing rate parameter T_(0.9) were 0.23 min,10.41 min,respectively.CONCLUSION: The ultra- micro porphyrization could not influent the real content and in vitro release of asperosaponin Ⅵ in Radix Dipsaci.But it could improve the releasing rate of asperosaponin Ⅵ.
ABSTRACT
Objective: To evaluate dissolution properties of 2 kinds of ambroxol hydrochloride tablets.Methods: A HPLC method was used.The column was Hypersil C 18 (10 ?m,150 mm?4.6 mm).The mobile phase was methnol water tetrahydrofuran triethylamine (71∶29∶2.5∶0.25).The wavelength of detector was 242 nm.Data were analyzed by Weibull's distribution model.Results: Both tablets dissolved rapidly and their dissolution rate reached 85% in the first 8 min.But there was significant statistic differences between the 2 tablets as for Weibull's parameters.Conclusion: Although the dissolution rate of 2 tablets is similar,there are still some differences between their dissolution parameters.The dissolution of the imported tablets is more rapid than the home made ones.
ABSTRACT
AIM:To compare the dissolution of asperosaponin Ⅵ between the ultra-micro powder and the fine powder of Radix Dipsaci.METHODS:The real contents,in vitro release and releasing rate of asperosaponin Ⅵwere determined by HPLC for the ultra-micro powder and the fine powder.RESULTS:In the ultra-micro powder and the ordinary powder,the real content of asperosaponin Ⅵ were 4.87%,4.74%,respectively;in vitro release in 1 h were 48.2 mg/g,47.5 mg/g,respectively;releasing rate parameter T_ 0.9 were 0.23 min,10.41 min,respectively.CONCLUSION:The ultra-micro porphyrization could not influent the real content and in vitro release of asperosaponin Ⅵ in Radix Dipsaci.But it could improve the releasing rate of asperosaponin Ⅵ.