The Study On The Interaction Of Water-soluble Chitosan With Bovine Serum Albumin

In this paper, the ineraction conditions of water-soluble chitosans(WSC) and bovineserum protein(BSA) were studied, It was determined that the best interaction conditions ofwater-soluble chitosans and bovine serum protein. The micro environment of water-solublechitosans and bovine serum protein which occurred was changed.The influence of water-soluble chitosans to the conformation of bovine serum protein wasstudied with characterized by the ultraviolet spectrum, the fluorescence spectra ofsynchronization and three-dimensional fluorescence spectrum and infrared spectral.The paper optimized the interaction conditions of water-soluble chitosans with bovineserum protein by sing lecritical success factors, then obtained the optimal pH value is6.37.The result shows that the inorganic salts, ionic surfactant and ethanol have influence to theinteraction of water-soluble chitosans with bovine serum protein.This paper optimized the interaction conditions of water-soluble chitosans with bovineserum protein by sing lecritical success factors, and obtain the optimal pH value is6.37.Thestudy found that the inorganic salts, ionic surfactant and ethanol has influence to theinteraction of water-soluble chitosans with bovine serum protein.System absorbance increased with the gradually increasing of inorganic saltconcentration, when the inorganic salt concentration is less than1.2mg/mL; systemabsorbance decreased with the increased of the inorganic salt instead concentration, when theinorganic salt concentration was more than1.2mg/mL.The cationic surfactants has a certain extent inhibition to the interaction of water-solublechitosans with bovine serum protein, while can also maintain the stability of solution. But thecharacteristics absorption peaks of bovine serum protein changed more, when the anionicsurfactant was carried into, so it can’t maintain stability of the system. System absorbance wasdecreased with the increasing of ethanol concentration.Fixed the water-soluble chitosans concentration and added different concentrations ofbovine serum albumin; fixed bovine serum protein concentration then added differentconcentrations of water-soluble chitosans, that measured its ultraviolet absorbance at280nm then found that: the BSA concentration and WSC concentration with absorbency A had goodlinear relationship, when the BSA concentration in0~1.5mg/mL and WSC concentration in0~1.5mg/mL. Its linear equation was A=1.36114+0.59848CBSA, R~2=0.9995; A=0.68019+1.57161CWSC, R~2=0.99973.The fluorescence quenching of WSC to BSA was static quenching. Their bindingconstant Ka=5.35×10~4L/mol, binding site was1.05. The influence of WSC on theconformation of BSA was analyzed by synchronous fluorescence spectra, three-dimensionalfluorescence spectrum and infrared spectrum, and the conclusion was that the maximumemission peak wavelength was shifted from285nm to287nm with the increase of WSCconcentration. Given suggestion that the combination of WSC and BSA which caused thatBSA tryptophan residues hydrophobic strengthening in the surrounding. Found thatwater-soluble chitosans with bovine serum protein had happen interaction through the infraredspectrum research.