Preparation Of PDA And SiO 2 Nanocaps And Its Application In Chiral Separation

Nanochannel technology, has made considerable progress since the nineties of the last century. The nanochannel has been extensively used in the fields of biomedicine, materials science, separation and biosensing because of its size effect on the structure, the surface area effect, the special physical and chemical properties of the channel surface.In this paper, the poly(dopamine)(PDA) and Si O2 nanochannels were prepared and characterized. The transportation of chiral substances through the functionalized nanochannel membranes was investigated. Compared with the traditional high performance liquid chromatography and capillary electrophoresis, the nanochannel technology shows to the special advantages in the separation of chiral substances.Details are presented in this thesis as follows:The dopamine were deposited within the pores of the polycarbonate(PC)template membrane by auto polymerization method. Modern characterization techniques were used to observe the morphology of the prepared nanotube array. The relationship between the deposition time and the pore size of the nanochannels was discussed by electrochemical methods. The characteristics of the nanochannels were investigated by the Zeta potential measurement, XPS,UV, FTIR and other methods. At the same time, the electrical resistance of the nanochannel membrane were investigated by the coupling of electrochemical workstation and eparation cell. The effect of p H, ionic strength and the pore size of the nanochannels on the electrical resistance of the nanochannel membrane were investigated..A chiral selector, chitosan, which can provide a chiral environment, was modified in the pores of the nanotubes. Based on the differences of transport rate between the phenylalanine enantiomer within the nanopore, the chiral enantiomer can be separated. The effect of p H value of the buffer solution, ionic strength of the buffer solution, the pore size of the nanochannels and the concentration of the target substance on the separation of chiral were investigated.L-cystine, a chiral selector providing a chiral environment, was modified in thepores of the nanotubes. Based on the differences of electrical resistance between the targets within the nanopore, the chiral D,L-phenylethylamine can be recognized.The effects of ionic concentration of the solution, the pore size of the nanochannels and the concentration of the target substance on the recognition of chiral D,L-phenylethylamine were investigated. At the same time, the optimal resolution of the enantiomer were investigated using Spectropolarimeter.Polycarbonate membrane were coated by PDA. The weak reducibility of PDA was used to reduce these absorbed [Ag(NH3)2]+ ions into silver nanoparticles immobilized on the PC-PDA surfaces. And then the silica were deposited within the pores of the PC-PDA-Ag template by st?ber sol-gel method. Modern characterization techniques were used to observe the morphology of the prepared nanotube array. The relationship between the deposition time and the pore size of the nanochannels was discussed. The characteristics of the nanochannels were investigated by the Zeta potential measurement, XPS and other methods. At the same time, the electroosmotic flow of the nanochannel were investigated.