[Study on andrographolide solid dispersion vectored by hydroxyapatite].

OBJECTIVE To prepare andrographolide solid dispersion, with hydroxyapatite as vector, in order to increase drug dissolution. METHOD 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. RESULT 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. CONCLUSION The prepared solid dispersions with hydroxyapatite as the vector can effectively improve the stability and dissolution of water-insoluble drug andrographolide.