Study On Sustained-Release Matrix Tablets Of The Complexs Of Total Alkaloids From Coptidis And Ion Exchange Resin

In this paper, The drug-resin complexes were prepared with organic bases from Rhizoma Coptidis have lots of physiological activity and weak acid cation exchange resin named IRP88 as the carrier, study of the preparation technology and relative mechanisms. The complexes as raw material, to selection the technology and prescription for sustained-release matrix tablets, study the release kinetics and mechanism in vitro. The studies were as follows:(1) Established a sensitive and reliable HPLC method for the analysis of raw materials, drug-resins and study the drug release in vitro , in order to provides a theoretical basis and methodological basis for preparation of the drug-resin complexes and sustained-release matrix tablets.(2) The drug-resin complexes were prepared by bath process, investigated the critical factor on the drug- exchange speed and extent, and the ion exchange reaction dynamics and thermodynamics have been studied. The exchange reaction between the drug and resin was accorded with first order kinetics reaction, and the free energy reduction, the process of entropy increase can be spontaneous. And ultimately determine the drug-resin preparation.(3) The combination mechanism of DRC was investigated by DSC, infrared analysis, X-ray which ascertained that the combination force between total alkaloids from Rhizoma Coptidis and resin was ionic bond interaction instead of physical adsorption interaction(4) The studies of the drug-resin complexes release in vitro showed that complexes can rapidly release in simulated gastric fluid; in simulated intestine, drug release from the resin particles was controlled by particle diffusion process according to Viswanathan's equation.(5) Using the method of all powder pellets, through the behaviors of drug release and fitting equation, screening a variety of sustained-release matrix material, the final selection Carbopol 974P NF resin as a matrix for the drug-resin complexes of sustained-release matrix tablets, and determine the dissolution process of the sustained-release tablets was zero-release ,controlled by erosion of matrix.