Study on preparation of papaverine-gelatin microspheres and its release in vitro

Objective To sustain drug concentration of papaverine in subarachnoid for treatment of vasospasm following subarachnoid hemorrhage and confirm whether controlled releasing system is appropriate for the prevention of vasospasm following subarachnoid hemorrhage.To prepare appropriate gelatin microspheres by optimizing experiment conditions,load them with papaverine and observe its release characteristics in vitro.Methods Degradable gelatin was used as a carrier with liquid paraffin as oil phase and Span-80 as emulsifier.Orthogonal experimental design was introduced to optimize the preparation conditions of the blank gelatin microspheres.Furthermore,papaverine gelatin microspheres were prepared using improved emulsified cold-condensation method.Results After optimizing,microspheres with good shape,smooth surface and narrow size distribution were prepared.The amount of drug carried by microspheres was 28%.Studies on the release in vitro showed that newly no initial burst release could be seen,the drug could be released slowly in two weeks.Conclusion The preparation procedure established was stable and practical,and the microspheres obtained showed good sustained-release characteristics.