Preparation And Evaluation Of Ginkgo Biloba Extract Double Pulsatile Capsules

Objective:To prepare the Ginkgo biloba extract double pulsatile capsules with advantages of easy application and good patient compliance and provide reliable method for quality evaluation.Method:Ginkgo biloba extract double pulsatile capsules were made up five parts:soluble capsule cap,insoluble capsule body,lag layer,separation layer and GBE fast release droppill.EC was taken as membrane material to prepare capsule bodies;mixture of sodium alginate and lactose were used to prepare lag layer;mixture of lactose and calcium hydrophosphate were used to prepare separation layer;mixture of Ginkgo biloba extract,stearic acid,PEG-4000 were used to prepare GBE fast release droppill.Investigation formula of lag layer to exsure proper lag time.Reaearch formula of separation layer to study drug release.Evaluation the GBE-DPC from appearance,the difference of filling quantity,content determination and the release.Establishment the UV content methods and HPLC fingerprint methods for determinating similarity of double pulse in-vitro from microcosmic perspectives respectively to evaluate release degree.Similarity was also taken as index in-vivo by HPLC fingerprint methods to establish the evaluation methodology.We selected New Zealand rabbit as laboratory animal which divided into two groups in random.Control group was given GBE fast release droppill and the test group was given the GBE-DPC,cross-over experiment was taken after washout period.We carried on in-vivo quality appraisal by comparing HPLC fingerprint of serum containing drug with similarity evaluation software.Result:With the incrase of the dose of lag layer and proportion of sodium alginate,the lag time was lengthened.The seperation layer affect the drug release.The GBE-DPC adopting the optimized formulation is clean and tidy,fast releae dropill with uniform size and same color,lag and seperation layer smooth and orderly.The limit of gross deviation is±7.5%,content of total flavonoids is 2.85±0.36%,lag time is 6.57±0.24h(n=6).The similarity of HPLC fingerprint is 0.96±0.014(n=6),which indicating that varieties of active ingredients can be released periodically?synchronously and completely.The similarity of serum containing drug collected from the control group and test group were 0.896 and 0.834 respectively.The GBE-DPC was given once can achieve the desired effect of GBE fast release dropill was given twice.Conclusion:By adjusting the dose of lag layer and proportion of sodium alginate can control the lag time.Adding seperation layer can increase drug release.GBE-DPC satisfy the requirement that about 6-7 hours delay for the second drug release and the similarity of ingredient and content of the two pulse is nice.The GBE-DPC which can replace the GBE dropill given twice has some advantages.