Study On Nitrobenzidine Penetration Pump Controlled Release Tablets

There is too much surfactant in use in the nifedipine release test. Even though the cumulative release in vitro is very well, the bioavailability in vivo is not the same as that in vitro. Here, the solid dispersion technique will be used in the push-pull osmotic pump tablets to enhance the solubility of nifedipine and the bioavailability in vitro.Nifedipine was chosen as the model drug. The formulation and preparation process of double-layer osmotic pump control-release tablet for drug with low solubility was studied. And the tablets’pharmacokinetics was studied with 4 dogs.First, the method of nifedipine assay and the drug release were established. Than the solubility of nifedipine in different solvent was tested, the figures are helpful. The stability in light is tested as well.PEO, PVP, and PEG 6000 were used in the preparation of the nifedipine solid dispersion. And different ratio of carrier/nifedipine was tested. PVP was established to be the carrier after testing the dissolubility、dissolution rate and DSC.In the formulation and preparation process research of double-layer osmotic pump control-release tablet containing nifedipine, single factor test had been done and was adopted to obtain the optimized formulation. The results showed that for the prepared tablet, nifedipine had been mostly released in 24h in-vitro and cumulative release percentage had exceeded 90%, with an obvious zero order release from 4h to 16h.With the LC-MS-MS, the pharmacokinetic study of the self-made osmotic tablets and references tablets were performed in four healthy dogs. The results indicated the bioavailability of the self-made tablets was a little higher.