Supercritical Fluid Technology Preparation Of Slow-release Preparation Technology Was Studied

Delayed release particles of acetaminophen were prepared by supercritical CO2. The particles’release and capsule’s release were also studied. This is a new method to prepare delayed release particles by supercritical fluid.UV detection was used to determine the content of acetaminophen. The factors’ effects on drug release were studied:excipient, ratio, supercritical CO2 temperature, supercritical CO2 pressure and the time. The optimal condition was:with X1 as excipient, the ratio of excipient and drug 1:1, supercritical CO2 temperature 45℃, supercritical CO2 pressure 15 MPa and experiment time 2 hours. In this condition, the release rate in 12 hours was 86.13%. The delayed release was optimal and fit the Pharmacopeia’s requirement.Aspirin was used to prove this technology’s applicability. The results showed that this technology was suitable for Aspirin. In the condition:with X1 as excipient, the ratio of excipient and drug 1:1, supercritical CO2 temperature 45℃, supercritical CO2 pressure 15 MPa and experiment time 1 hour, the release rate in 12 hours was 55.95%. So this technology was suitable for preparation of Aspirin particles.The particles prepared in optimal condition were encapsulated and delayed release capsule was obtained. The results indicated that the release rate of the capsule in 12 hours was 92.75%.