Uniform-sized amino-modified silica nanopar-ticles have been prepared by the controlled synchronous hydrolysis of tetraethoxysilane and N-(?amimoethyl)-- aminopropyltriethoxysilane in water nanodroplet of the wa-ter-i...Uniform-sized amino-modified silica nanopar-ticles have been prepared by the controlled synchronous hydrolysis of tetraethoxysilane and N-(?amimoethyl)-- aminopropyltriethoxysilane in water nanodroplet of the wa-ter-in-oil microemulsion. These nanoparticles display posi-tive charge potential at definited pH. This is due to the pres-ence of amino groups on the surface of the nanoparticles. Nanoparticles-plasmid DNA complexes can easily form through electrostatical binding between the positive charges of the amino-modified silica nanoparticles and the negative charges of the plasmid DNA. The complexes can be also dis-sociated under alkaline pH or high ionic strength conditions. And enzymatic digestion of the plasmid DNA is almost in-hibited by these nanoparticles complexes. A novel non-viral gene carrier based on the amino-modified silica nanoparti-cles is proposed under the combination of nanotechnology, biotechnology and gene engineering technology. The plasmid DNA can successfully cross various systemic barriers to COS-7 cells as well as mediate high expression of Green Fluorescence Protein (GFP) gene in cells by use of this novel gene carrier.展开更多
Au nanotubules (channels) can be electrolessly plated within the pores of polycarbonate microporous filtra-tion membranes. When an electric field was applied on the cell consisting of the membrane and Pt electrodes, t...Au nanotubules (channels) can be electrolessly plated within the pores of polycarbonate microporous filtra-tion membranes. When an electric field was applied on the cell consisting of the membrane and Pt electrodes, the re-sponse current decreased due to a baffle effect from big molecules when the electrolyte ion and big molecules passed through the channels modified with chemical groups. Based on this principle, a nanotubules-based sensing technique has been developed. This method can be applied to the determi-nation of human IgG with a detection limit of 0.34 ng/mL.展开更多
A novel method has been developed to monitor the nucleic acids ligation process. Molecular beacon was employed here to convert the ligation information into fluorescence signal quickly and quantitatively. This method ...A novel method has been developed to monitor the nucleic acids ligation process. Molecular beacon was employed here to convert the ligation information into fluorescence signal quickly and quantitatively. This method provides effective and original approach to researching the dynamic ligation process and the interactions between nucleic acids and ligase. An analytical method for T4 DNA ligase based on this way has been built up with a linear detection range from 2.3×10?4 U/mL to 0.23 U/mL. It is rapid and sensitive to detect 2.8×10?5 U T4 DNA ligase in 10 min.展开更多
基金supported by the Pre-Key Project of Basic Research of Ministry of Science and Technology of the People’s Republic of China(Grant No.2001-51)the Key Project of the National Natural Science Foundation of China(Grant No.20135010)+4 种基金the National Outstanding Youth Foundation of China(Grant No.29825110)the Key Project Foundation of the Education Ministry of China(Grant No.2000-156)the Leading Teacher Foundation of the Education Ministry of China(Grant No,2000-65)the Oversea Youth Scholar Co-research Foundation of China(Grant No.20028506)the Natural Science Foundation of Hunan Province(Grant Nos.00GKY1011 and 01JJY2012)
文摘Uniform-sized amino-modified silica nanopar-ticles have been prepared by the controlled synchronous hydrolysis of tetraethoxysilane and N-(?amimoethyl)-- aminopropyltriethoxysilane in water nanodroplet of the wa-ter-in-oil microemulsion. These nanoparticles display posi-tive charge potential at definited pH. This is due to the pres-ence of amino groups on the surface of the nanoparticles. Nanoparticles-plasmid DNA complexes can easily form through electrostatical binding between the positive charges of the amino-modified silica nanoparticles and the negative charges of the plasmid DNA. The complexes can be also dis-sociated under alkaline pH or high ionic strength conditions. And enzymatic digestion of the plasmid DNA is almost in-hibited by these nanoparticles complexes. A novel non-viral gene carrier based on the amino-modified silica nanoparti-cles is proposed under the combination of nanotechnology, biotechnology and gene engineering technology. The plasmid DNA can successfully cross various systemic barriers to COS-7 cells as well as mediate high expression of Green Fluorescence Protein (GFP) gene in cells by use of this novel gene carrier.
文摘Au nanotubules (channels) can be electrolessly plated within the pores of polycarbonate microporous filtra-tion membranes. When an electric field was applied on the cell consisting of the membrane and Pt electrodes, the re-sponse current decreased due to a baffle effect from big molecules when the electrolyte ion and big molecules passed through the channels modified with chemical groups. Based on this principle, a nanotubules-based sensing technique has been developed. This method can be applied to the determi-nation of human IgG with a detection limit of 0.34 ng/mL.
文摘A novel method has been developed to monitor the nucleic acids ligation process. Molecular beacon was employed here to convert the ligation information into fluorescence signal quickly and quantitatively. This method provides effective and original approach to researching the dynamic ligation process and the interactions between nucleic acids and ligase. An analytical method for T4 DNA ligase based on this way has been built up with a linear detection range from 2.3×10?4 U/mL to 0.23 U/mL. It is rapid and sensitive to detect 2.8×10?5 U T4 DNA ligase in 10 min.
