Lysozyme-phosphotungstic Adid Self-Assembled Composites:formation Mechanism And Application

Phosphotungstic acid(PTA)is an negatively charged oxygen-containing polyacid.Lysozyme(LYZ)is a globular protein comprising many positively charged amino residues on its surface.A series of LYZ-PTA hybrid materials from the self-assembly of LYZ and PTA were prepared.The LYZ-PTA material has a potential application in catalysis,photodynamic therapy,and sensing.LYZ-PTA hybrid material were characterized with scanning electron microscopy,infrared spectroscopy,X-ray photoelectron spectroscopy and inductively coupled plasma optical emission spectrometry.The results show that the morphology of LYZ-PTA material can be adjusted by changing the concentration of phosphotungstic acid solution.The interaction mechanism of LYZ with PTA was investigated by two-dimensional Fourier transform infrared spectroscopy(2D-FTIR).The residues and structures of lysozyme that have preferential interactions with PTA have been identified.LYZ-PTA was used as an adsorbent for encapsulating methylene blue(MB).The adsorption characteristics of MB were investigated with respect to the changes in initial MB concentration.The adsorption kinetics were analyzed using pseudofirst-order and pseudosecond-order model.The adsorption data were well described by the pseudosecond-order model.The equilibrium adsorption data were interpreted with Langmuir isotherm model.The monolayer adsorption capacity of LYZ-PTA was found to be 256.4 mg/g.LYZ-PTA material was applied to catalyst the reaction of fructose to 5-ethoxymethylfurfural.The effects of reaction temperature,reaction time and solvent ratio on the product distribution were explored.60.1%of EMF yield can be achieved.