The Nature Investigation And The Loading Mechanisms Study Of A Potential Pharmaceutical Excipient Ion-exchange Fiber

The purpose of this thesis was to investigate the ion-exchange fiber’s the features,the drug’s loading and releasing rules and the application in the fields in the pharmaceutics.So as to preliminarily explore a route for this potential pharmaceutical excipients’development and application.The strong acid polyvinyl alcohol cation-exchange fiber was prepared by using polyvinyl alcohol fiber.The influence factors of the preparation were investigate.The strong acid polyvinyl alcohol cation-exchange fiber was prepared by two different methods with optimized preparation technology.The ion exchange capacity of the strong acid polyvinyl alcohol cation-exchange fiber prepared by acetalation-carbonization-sulfonation preparation technology was about 2.0 mmol/g.On the other hand,the ion exchange capacity of the strong acid polyvinyl alcohol cation-exchange fiber prepared by benzaidehyde sulfonate sodium acetalation preparation technology was about 0.5 mmol/g.The properties of the ion-exchange fibers and the drugs used in this thesis were studied.The microcosmic outward appearance,fiber’s strength,hydrophilicity,ion exchange capacity,swelling degree and density of the ion-exchange fibers were investigated.The analytical method,dissolubility,dissociation constant,hydrolysis constant and coefficient of partition between oil and water of the drugs were investigated too.The rules of the drugs loading onto and releasing from the ion-exchange fibers were investigated in this thesis.The results showed that the behaviours of loading were influenced by the properties of the drugs,the structure of the ion-exchange fibers,temperature,agitating strength and drug’s concentration.The behaviours of releasing were influenced by the properties of the drugs,the structure of the ion-exchange fibers,temperature,agitating strength,the category and concentration of the releasing medium.The solubilization of the ion-exchange fiber for drugs with poor water solubility was investigate preliminarily in this thesis.The drugs with poor water solubility and the ion-exchange fibers combined together through acid-base reaction.The results of the structure identification showed that the drug and the ion-exchange fiber were combined with ionic bond.There was no drug crystal on the surface of the ion-exchange fibers.The drugs were dispersed highly on the surface of the ion-exchange fibers.The results of the dissolution test showed that the dissolution of the drug ion-exchange fiber complex was higher than that of the drug solution not only in dissolution rate but also in dissolution amount.The drug ion-exchange fiber complex had the dissolution enhancement for the drugs with poor water solubility.This dissolution enhancement was not influenced by the pH of the dissolution medium,which displayed a typical feature of the ion exchange reaction.The behaviours of the ion-exchange fiber improving the iontophoresis were investigated.The results showed that ion-exchange fibers could improve the iontophoresis.This improvement was influenced by current strength and the amount of the drug loading on the fibers.When the amount of the drug loading on the fibers reached or near to the ion exchange capacity this improvement was obvious.The amount of the drug that imported by iontophoresis of the drug ion-exchange fiber complexes with the saturation drug loading amount was higher than that of the drug solution.In the in vivo experiment,both drug cation-exchange fiber complex and drug anion-exchange fiber complex displayed the improvement for iontophoresis.The area under the curve of the drug plasma concentration of the drug ion-exchange fiber complex was obviously larger than that of the drug solution.