Study On Blending Drug Release Carrier Of Konjac Glucomannan-modified Starch

This paper use Konjac glucomannan (KGM) and modified starch as blendmaterials, to prepare KGM/modified starch mixed gel; And use captopril as modeldrugs, to prepare KGM/modified starch drug loading hydrogel and study ofKGM/modified starch drug loading hydrogel as colon-specific drug delivery hydrogel;To analyse the solvent-dissolve behavior of KGM/modified starch mixed gel, drugrelease behavior of KGM/modified starch drug loading hydrogel and colonpositioning of drug release in solution. this paper analyses the swelling-dissolveperformance of KGM/modified starch mixed gel and KGM/modified starch drugloading hydrogel in different conditions, and a good colon positioning of drug releasesystem has been established. the experimental results are as follows:(1)In this paper, the KGM/modified starch blending gel is preparated withKGM and modified starch as materials. Investigate the swelling-dissolve behavior ofKGM/modified starch mixed gel in different affecting factors, studies show that,KGM/modified starch blending gel′s swelling-dissolve behavior can be divided intothree stages in pH7.0buffer solution, namely, bibulous swelling stage, swellingbalance stage and dissolve stage, the study found that KGM/modified starch blendinggel in stages of bibulous swelling stage had roughly the same time, and swellingbalance time and dissolved time of KGM/modified starch was different with thechange of blend of gel ratio, different proportion of mixed gel,concentration,andKGM viscosity.In the influential factors of this experiment, different proportion of mixed gel,the total amount of the polysaccharide, and pH value of the medium of solution have amajor influence in mixed gel`s Swelling-dissolve behavior. KGM or modified starchalone hydrogel were have maximum and minimum swelling of degrees for93%and31%; In the two kinds of polysaccharide blending hydrogel, the bibulous rate of geland swelling degree increased obviously with the increase of the content of the KGM;In this experiment, the mixed gel`s swelling degree increased with the increase of theconcentration of the total polysaccharide; The pH value of the solution medium have significant effect on the KGM/modified starch mixed gel`s swelling-dissolve behavior.and the results show that, KGM/modified starch mixed gel`s solvent-dissolvebehavior has the obvious inhibition in pH1.2solution medium, and in pH6.8and7.4buffer solution, KGM/modified starch of mixed gel swelling degree and dissolvingrate has increased significantly; The viscosity of the KGM effect larger onKGM/modified starch mixed gel`s dissolving rate, while modified starch viscosity hasnot affect on KGM/modified starch mixed gel`s solvent-dissolve performance.(2) The found of the KGM/modified starch drug loading hydrogel show that drugrelease process can be divided into three stages of KGM/modified starch drug loadinghydrogel: in the early drug release stage, the gel drug release time is shor tand thedrug release rate quickly; The middle drug release stage, drug release rate slower thanthe early drug release stages; End of drug release stage, the gel`s drug releasecomplete basic,drug`s accumulated release rate increase is not obvious.The ratio between polysaccharide, polysaccharide total concentration, drugparticle size, KGM viscosity, the pH value of the medium is influence KGM/modifiedstarch drug loading hydrogel drugs release rate to some extent. gel formed By KGMalone drugs released in full within14h and formed by a single modified starch in drugloading hydrogel in24of drug release cumulative percentage is only32%; In the twokinds of polysaccharide blend drug carrier gel, there is the best of drug release ratewhen the rate of KGM: modified starch1s7:3in24hours; Along with the increase oftotal polysaccharide concentration, the drug release rate of KGM/modified starch isslower; The drug size of CAP have also obvious influence the release behavior of theKGM/modified starch drug carrier gel, the greater the drug particle size, the greaterthe drug release rate, at the same time, drug release rate of drug carrier gel is alsoaffected by the nature of the drugs'; In drug carrier gel drug release rate slow with theKGM viscosity increases, and modified starch viscosity has little affect the behaviorof drug release; KGM/modified starch drug carrier gel`s drug release behavior has apH responsiveness, high acid medium can obvious block drug release inKGM/modified starch drug carrier gel.(3) In the KGM/modified starch drug carrier gel as colon positioning of drug release the system the research found that the gel preparated by KGM alone havegood response to theβ-mannanase, but the block effect of drug dissolution is notideal in the Upper gastrointestinal; And the gel preparated by modified starch alonehas almost not ring toβ-mannanase that can effectively prevent the leakage of drugrelease drugs; To mix KGM and modified starch as blending drug carrier gel as colonpositioning of carrier experiments show that the gel with different proportion anddifferent concentrations have different effect on the block of drug release, theresponse to the enzyme is different also, of which added0.003g CMS, drugs inprevious release rate is no more than5%, and in the simulation of colon fluids thedrug release rate of the gel can reach62%, therefore0.50g KGM70added0.003gCMS system is an ideal location of the colon of drug release system.