Application of Single Solid State Nanopore / Nanochannel Based on Polymer Membrane and Glass Nanopipette in Analytical Chemistry / 分析化学

Nanopore / nanochannel sensing technique drawing more attention in analytical chemistry due to its unique advantages and the fabricated electrochemical sensors and electrochemical responsive gates have been widely used for more target detection, including single molecule protein and DNA sequencing. Nanopore /nanochannel that used for fabricating electrochemical detection system is mainly divided into biological nanopore and solid state nanopore, and among them, solid state nanopore / nanochannel has a wide range of application due to its inherent properties, such as easy for modification, good mechanical property and stability. Resistive pulse sensing and current-voltage curves (ion current rectification) are two main methods of nanopore / nanochannel sensing technique used for target analysis, so in this review, we introduced the fundamentals and applications of nanopore sensing technique based on the above two methods. In addition, we concluded the application and development of single state nanopore / nanochannel in recent years, and also gave a brief look at the future challenges and prospects in the development of this field.

Development of Biological Nanopore Technique in Non-gene Sequencing Application / 分析化学

Nanopore technique is a low-cost, ultrafast method for single-molecule level analysis without labels. Nanopore technique was first proposed more than 20 years ago and exhibited an excellent potential in DNA sequencing. So far, the commercial development of nanopore strand-sequencing as a portable device has been realized. Meanwhile, a remarkable number of studies have demonstrated that nanopore represents versatile single-molecule sensors for a wide range of molecule. Therefore, in this article we mainly review the use of nanopore technique based on the interface interactions between biological pore and the analytes such as protein/peptide to obtain kinetic and thermodynamic information at single-molecule level. And a large number of biological molecules and metal ions are quantitatively detected by nanopore analysis, allowing its development for the future biotechnologies and medicine applications. Besides, electrochemical detection system is crucial to nanopore technique. Therefore, we focus on advancements in relative software and ultralow current instrumentations with high-bandwidth.

Chiral Separation and Identification of D,L-Histidine Based on Nanochannels Membrane Coupling with Surface Enhanced Raman Scattering Spectroscopy / 分析化学

Gold nanochannels were prepared using Al2 O3 nanotubules membrane as the carrier and modified with chitosan by a classical N-(3-dimethylaminopropyl)-N-ethyl carbodiimide ( EDC)/N-hydroxysuccinimide ( NHS ) coupling reaction. The nanochannels were characterized by field emission scanning electron microscopy ( FESEM) , cyclic voltammetry and AC impedance method. The Au nanochannels modified with chitosan showed a chiral environment and can be used to separate histidine enantiomer. The effects of pore size and solution pH on the separation efficiency of histidine were investigated. To increase the detection sensitivity of D-, L-histidine, Ag nanoparticles were used to enhance the surface enhanced Raman scattering ( SERS) activity. The results showed that the chitosan-modified gold nanochannels can be used to separate chiral histidine based on this unique selective nanochannel membrane. L-Histidine and D-histidine were respectively detected by SERS at wavelengths of 1000 and 1590 cm-1 . The results showed that L-histidine and D-histidine were separated well in the mixture containing 200 μL of histidine, 100 μL of colloidal Ag and 100 μL of 80 mmol/L NaCl ( pH=7 . 59 ) with a separation efficiency of 4 . 91 .