β-cyclodextrin modified silica nanochannel membrane for chiral separation

The silica nanochannel membrane were prepared by sol–gel template synthesis method. The morphology of the nanochannels, characterized by field emission scanning electron microscope, showed that the SiO2 nanochannel wall was smooth and uniform. The characteristics of the nanochannels were investigated by the Zeta potential measurement, XPS and other methods. The inner wall of the silica nanochannels was modified with β-cyclodextrin (β-CD) and characterized by cyclic voltammetry and AC impedance method. The modification of β-CD provided a chiral environment for the separation of tryptophan enantiomer. The effects of pH and the pore size of the nanotubules on the separation of tryptophan enantiomers were investigated. The β-CD-modified SiO2 nanochannels was verified by the separation of chiral tryptophan.