Study On Konjac Glucomannan-Polyvinyl Alcohol Film As Colon-targeted Drug Delivery Carrier

Hydrogel systems of Konjac glucomannan (KGM) and Polyvinyl Alcohol (PVA) crosslinked with Sodium Tripolyphosphate (STPP) were prepared in this thesis for colon-targeting drug delivery. Based on the single factor experiment, the orthogonal experiment was used to optimize the technology. The amount of the crosslinker STPP, the blender of PVA and the plasticizer of glycerol ,s influence to the balance swelling and the response of the enzyme were studied .The Fourier transformed infrared spectra(FTIR), X-ray diffraction and the differential scanning calorimeter (DSC) were used to analyze the interaction between materials and the cross-linking mechanism. Using Bovine Serum Albumin (BSA)as a model drug, the amount of the crosslinker, the blender and the plasticizer's influence to the release of the drug were studied. The release mechanism was discussed and the dynamic release model wasestablished. Then, fit the equation and discuss the parameters. The main conclusions in this thesis were drawn as following:(1)The optimum reaction conditions of preparing KGM-PVA-STPP hydrogel were as following: the concentration of KGM was 1%w/w, pH value 11, n(STPP):n(KGM)=0.6-1, m(NaCl):m(KGM)=1-3%w/w,m(PVA):m(KGM)=0.5-1.5%w/w,the concentration of glycerol was 6%ml/ml ,the reaction time was 3 hours and the reaction temperature was at room temperature.(2)The Fourier transformed infrared spectra(FTIR), X-ray diffraction and DSC tests results showed that:In the KGM-PVA-STPP hydrogel,there were stronger hydrogen bond interaction and phospholipids bond in the KGM-PVA-STPP hydrogel.At the same time , the acetyl which is related with the response of the enzyme was reserved in the KGM-PVA-STPP hydrogel. KGM and PVA engendered clear interaction by STPP's bridging role. KGM and PVA had good Compatibility and formed a IPN in the cross-linked hydrogel.(3)The drug release experiment results showed that:With the amount of Cross-linker of STPP and the blender of PVA increase, the drug release rate decreased. The amount of plasticizer glycerol didn,t have much affect on the drug release rate. (4)The drug release pattern of the Matrix film in the solution with enzymes was given. The basic assumptions were established. The derived release models are as follows:In the solution without enzymes: The one order-degradation drug release model:The two order-degradation drug release model:In the solution with enzymes, the zero order-degradation drug release model fitted better.