Preparation And Characterization Of Lauryl Betaine And Pectin Composite Microspheres

This paper studied on lauryl betaine (BS-12) to solve the problem of pectin colon positioning dosing system drug release ahead of time. Lauryl betaine and pectin composite microspheres were prepared by using pectin as the carrier,indomethacin (IDM) as the model drug, Cacl2 and ZnCl2 as cross-linkings agent, lauryl betaine as the modifier to improve the hydrophobic performance of pectin. Then its performance of drug loading and drug release and the modification effect of lauryl betaine on pectin system were investigated.The gel beads were prepared by dripping method. According to the single factor experiment, the prescription was optimized, regarding the mass ratio of BS-12 to pectin, the mass ratio of IDM to pectin, NaOH concentration, pectin concentration crosslinking agent concentration and pH as the process parameters. The morphology of the gel beads was studied by SEM and the IDM content was determined by by Ultraviolet Spectrophotometry.This subject investigated the modified pectin calcium system and pectin zinc system by BS-12, and studied their performance. Results are follows:The optimal formulation and performance of lauryl betaine and pectin calcium composite microspheres:the pectin concentration was 4%,the mass ratio of BS-12:Pectin was 2.1:4, the mass ratio of IDM:Pectin was 1.8:4, NaOH concentration was 4%, CaCl2 concentration was 6% and pH was 1.In the pectin calcium system, the microspheres were homogeneous spherical with diameter of 0.8-1.12 mm, mass of 0.61-1.05 mg. The medicine carrying of pectin calcium was good, the drug-loading rate would increased to 19.61% from 8.52%, the encapsulation efficiency would increased to 92.82% from 33.89%. The slow release effect of pectin calcium was good, the cumulative drug release rate in 8h was fell to 14.39% from 59.34%, which continued to test in simulated colon environment until to 36h, the cumulative drug release rate would increased to 78.86% from 24.49%.The optimal formulation and performance of lauryl betaine and pectin zinc composite microspheres:the pectin concentration was 5%,the mass ratio of BS-12:Pectin was 2.1:4, the mass ratio of IDM:Pectin was 1.8:4, NaOH concentration was 4%, ZnCl2 concentration was 8% and pH was 4.In the pectin zinc system, the microspheres were homogeneous spherical with diameter of 0.96-1.20 mm, mass of 0.76-1.50 mg. The medicine carrying of pectin zinc was good, the drug-loading rate would increased to 8.96% from 2.37%, the encapsulation efficiency would increased to 49.01% from 11.54%. The slow release effect of pectin zinc was good, the cumulative drug release rate in 8h was fell to 7.30% from 56.33%, which continued to test in simulated colon environment until to 36h, the cumulative drug release rate would increased to 62.25% from 29.32%.The stability experiment showed that the stability of IDM in lauryl betaine pectin composite microsphere was better than IDM and that in pectin microspheres.