title: [Influence of solid dispersion technique combination on dissolution of tanshinone IIA].
abstract: OBJECTIVE
  To compare the influence on the dissolution of tanshinone IIA (TS IIA) solid dispersions in complex carriers and single, which used in preparation of TS IIA solid dispersions, and further enhance the dissolution of TS IIA.
  
  
  METHODS
  The TS IIA solid dispersions were prepared by solvent technique with polyvinylpyrrolidone K30 (PVPK30), poloxamer188 (F68) and combination of PVPK30 and F68 as carriers, respectively. The physical characteristics of TS IIA solid dispersions was studied using differential scanning calorimetry (DSC). Dissolution rates were studied using small cup method (CHP XC III). The solubility of TS IIA with the solid dispersions and pure drug form were determined by HPLC method.
  
  
  RESULTS
  The DSC analysis suggested that TS IIA was dispersed as an amorphous form in the combination of PVPK30 and F68. Dissolution profile of the prepared solid dispersions could be described by Weibull equation (R>0.99). For tested three carries, Td value (calculated time to 63.2% of total drug release according to Weibull equation) were (90.40 +/- 2.82) min, (204.5 +/- 8.20) min and (25.83 +/- 0.13) min, respectively. The PVPK30/F68-TS IIA solid dispersion resulted in a significant increase of TS IIA solubility compared with prepared PVPK30-TS IIA and F68-TS IIA solid dispersions (P<0.01).
  
  
  CONCLUSIONS
  As compared to single use of PVPK30 or F68, the combination of PVPK30 and F68 improve the dissolution rate and solubility of TS IIA significantly in the prepared solid dispersions (P<0.01). The application of complex carriers in solid dispersion technology should be paid more attention to improvement of poorly soluble drugs dissolution in the future.
authors.affiliation: West China School of Pharmacy, Chengdu 610041, China.
authors.forename: Juyong
authors.initials: J
authors.lastname: Yuan
authors.forename: Shengjun
authors.initials: S
authors.lastname: Mao
authors.forename: Qianwan
authors.initials: Q
authors.lastname: Shen
authors.forename: Shixiang
authors.initials: S
authors.lastname: Hou
authors.forename: Yingju
authors.initials: Y
authors.lastname: He
mesh_terms: D045784:Abietanes; D010616:Phenanthrenes / Q000737:chemistry*; D012995:Solubility; D013696:Temperature
chemical_list: D045784:Abietanes; D010616:Phenanthrenes; C021751:tanshinone