Mesoporous TiO₂ with different selectivities of protein immobilization performance

Mesoporous TiO₂ with adjustable pore diameter, high specific surface area and excellent biocompatibility has a good application prospect in biological molecules immobilization carriers. Mesoporous TiO₂-500 were prepared as the stationary phase packing in High Performance Liquid Chromatograph by calcinating H₂Ti₂O₅ at 500°C, and the TiO₂ samples were characterized by X-ray diffraction (XRD), N₂ adsorption-desorption and field-emmission scanning electron microscopy (FESEM). The residence time under different pH of bovine serum albumin, myoglobin and lysozyme through the new chromatograph column were tested. Nearly all three kinds of proteins were immobilized at pH=4.7, and the order of residence time of three proteins was lysozyme ≤ myoglobin ≤ bovine serum albumin under the condition of pH=7.4 and 11. Adsorption of three kinds of proteins on the surface of the mesoporous TiO₂-500 under atmospheric pressure was consistent with chromatographic results, and the order of the immobilization capacity of mesoporous TiO₂-500 for three kinds of proteins was lysozyme ≤ myoglobin ≤ bovine serum albumin. Therefore, due to the significant difference in protein immobilization performance, the mesoporous TiO₂ has a potential application in protein adsorption and separation, immobilizing enzyme and other fields.