Migration Characteristics Of Atrazine In The Nanochannel

Nanochannel is the pore or tubule with diameter from 0.1 to 100 nm. Nanochannel technique is exhibiting the great advantage in the fields of material science, chemistry, biology and medical science due to the size effect and chemical physical characteristics. Nowadays, nanochannel technique mainly refers to the nanochannels preparation, the transport of molecules through the nanochannels and related applications. This paper studied on the preparation process of nanochannels, the migration mechanism of pesticide through channels and the separation of these substances by nanochannel technique.Atrazine, as the widely used herbicide, is one of the main environmental pollutants because it can be eluted easily by the rainwater. So it is important to develop sensitive, convenient and effective methods with high resolution for the pesticide residue analysis. Generally, herbicide is often separated and detected by gas chromatography-mass spectrometry, high performance liquid chromatography, liquid chromatography-mass spectrometry and supercritical fluid chromatography. Contrast to these analysis methods, nanochannel technology is more effective and has better performance. However, there are few reports on pollutants analysis by nanochannel technique. Details are presented in this work as follows:(1) An electroless deposition method was used to deposit gold within the pores of the polycarbonate template membrane and Au nanochannels with different diameters were obtained. The factors affecting the deposition process were studied. Ultraviolet spectroscopy, scanning electron microscope, transmission electron microscope were used to characterize the pore size and the surface appearance. The size of the pore can be precisely controlled with high reproducibility by changing the deposition conditions.(2) The gold nanochannels become hydrophobic by modifying monolayer of self-assembled thiol (HSC18H37) and can be used as very good molecular filters forbidding paraquat and allowing atrazine to transport through the membranes. Atrazine and paraquat can be completely separated based on this hydrophobic membrane.(3) Octadecyl thiol (HSC18H37) was self-assembled on the Au nanochannels of polycarbonate template membrane. However, this hydrophobic membrane can be changed in response to the presence of some surfactants. The effects of different surfactants on the change of hydrophobicity of the membrane were studied here and possible reasons of this change were also discussed.(4) The capture antibody, atrazine-antibody, was modified onto the inner wall of Au nanotubules by glutaraldehyde interlinking method. Atrazine and paraoxon-ethy was separated by the nanotubule membrane with appropriate pore sizes, pH and ionic strength based on the immunoreactions between antibody and antigen.In summary, we developed some new approaches to separate and analyze pesticide by nanochannels in combination with conventional detection methods. Some mechanisms in the transport process were proposed. We can expect to provide some theoretical support for more widely practical application of nanaochannels.