title: [Study on andrographolide solid dispersion vectored by hydroxyapatite].
abstract: OBJECTIVE
  To prepare andrographolide solid dispersion, with hydroxyapatite as vector, in order to increase drug dissolution.
  
  
  METHODS
  Andrographolide and hydroxyapatite were dispersed in 95% ethanol. The solvent evaporation method was adopted to prepare andrographolide solid dispersion, in order to study its dissolution behavior, stability and physical characteristics.
  
  
  RESULTS
  The solid dispersion prepared with andrographolide and hydroxyapatite with the proportion of 1:8 existed in the vector in an amorphous form, according to differential scanning calorimetry, scanning electron microscopy and X-ray powder diffraction. The in vitro dissolution of andrographolide solid dispersions was up to 93% at 45 min. After the accelerated stability test for three months, the drug dissolution and content in andrographolide solid dispersion showed no significant change.
  
  
  CONCLUSIONS
  The prepared solid dispersions with hydroxyapatite as the vector can effectively improve the stability and dissolution of water-insoluble drug andrographolide.
authors.affiliation: Key Laboratory of New Drug Delivery System of Chinese Materia Medica, Jiangsu Provincial Academy of Chinese Medicine, Nanjing 210028, China. hsy872805820@163.com
authors.forename: Shao-Ying
authors.initials: SY
authors.lastname: Hu
authors.forename: Zhen-Hai
authors.initials: ZH
authors.lastname: Zhang
authors.forename: Xiao-Bin
authors.initials: XB
authors.lastname: Jia
mesh_terms: D002152:Calorimetry, Differential Scanning; D004224:Diterpenes / Q000737:chemistry*; D004339:Drug Compounding / Q000379:methods*; D004355:Drug Stability; D004365:Drugs, Chinese Herbal / Q000737:chemistry*; D017886:Durapatite / Q000737:chemistry*; D000431:Ethanol / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D015203:Reproducibility of Results; D012995:Solubility; D012997:Solvents / Q000737:chemistry; D013997:Time Factors; D014867:Water / Q000737:chemistry; D014961:X-Ray Diffraction
chemical_list: D004224:Diterpenes; D004365:Drugs, Chinese Herbal; D012997:Solvents; D014867:Water; D000431:Ethanol; C030419:andrographolide; D017886:Durapatite