Atomic force microscopy (AFM) was employed to quantitatively detect the interaction between a transcription factor, ZmDREBIA, and its target DNA sequence (DRE).The specificity of the interaction was revealed by compar...Atomic force microscopy (AFM) was employed to quantitatively detect the interaction between a transcription factor, ZmDREBIA, and its target DNA sequence (DRE).The specificity of the interaction was revealed by comparing the binding probability of ZmDREBIA to DRE element with core sequence ACCGAC and to the ERE element with core sequence AGCCGCC. Moreover, the single-molecular unbinding force between ZmDREBIA and DRE element was determined using Poisson statistical method to be 99±9 pN.The results indicated that AFM could serve as a sensitive and reliable technique to probe the interaction properties of the transcription factor and DNA element at single-molecular level, thus indicating that AFM is advantageous over the traditional methods, such as the electrophoretic mobility shift assay, regarding to the functional analysis of transcription factors.展开更多
The composite material of poly-(L-lactide) (PLLA) and carbon nanotubes (CNTs) were prepared. Itssurface morphologies and property were worked out by us-ing atomic force microscopy (AFM) and contact angle meas-urement....The composite material of poly-(L-lactide) (PLLA) and carbon nanotubes (CNTs) were prepared. Itssurface morphologies and property were worked out by us-ing atomic force microscopy (AFM) and contact angle meas-urement. Moreover, the prime cytocompatibility was used to investigate the biocompatibility of the composite materialcontaining CNTs and the effects of CNTs on one aspect of cell function, cell affinity. The results obtained indicate that thecomposite material of PLLA and CNTs possesses good bio-compatibility for both the 3T3 fibroblasts and Oct-1 os-teoblast-like cells. The addition of CNTs will greatly affectcell affinity of the material, which may be disadvantage for the cell adhesion.展开更多
Well-defined and controllable one-dimensional (1D) nanostructures of fullerene derivative have been pre- pared by an electrophoretic template synthesis method. The clusters of fullerene derivative formed in mixed solv...Well-defined and controllable one-dimensional (1D) nanostructures of fullerene derivative have been pre- pared by an electrophoretic template synthesis method. The clusters of fullerene derivative formed in mixed solvents are introduced into the channels of porous alumina templates through a dc electric field. Four types of 1D nanostructures (solid nanowires, solid-wall nanotubes, porous nanowires and porous-wall nanotubes) have been obtained by changing the deposition parameters. This approach opens a new avenue to assemble fullerene derivatives, endohedral fullerenes, as well as other functional organic compounds, which can form clusters in 1D nanostructure arrays for applications in chemical sensors, light energy conversion devices and nano- scale electronic and optoelectronic devices.展开更多
The adsorption and assembling of bacterio-chlorophyll c (BChl c) on a highly oriented pyrolytic graphite (HOPG) surface have been investigated by the scanning tunneling microscopy (STM). BChl c molecules are found to ...The adsorption and assembling of bacterio-chlorophyll c (BChl c) on a highly oriented pyrolytic graphite (HOPG) surface have been investigated by the scanning tunneling microscopy (STM). BChl c molecules are found to self-organize a well-defined adlayer on HOPG surface with a monomeric structure different from the dimer association seen on adlayers of Chls a, c and BChlide c, d. A structural model is proposed for the adlayer.展开更多
An important precursor 4,5-didodecylthiolph- thalonitrile (DCP) for synthesis of phthalocyanines (Pcs) and subphthalocyanines (SubPcs) was synthesized and the as-sembling structure of this molecule on the basal plane ...An important precursor 4,5-didodecylthiolph- thalonitrile (DCP) for synthesis of phthalocyanines (Pcs) and subphthalocyanines (SubPcs) was synthesized and the as-sembling structure of this molecule on the basal plane of highly oriented pyrolytic graphite (HOPG) surface was characterized using the scanning tunneling microscopy (STM) in ambient conditions. In high-resolution images of the molecules, we found that the arrangement of the cyano groups forms a head-to-head configuration to keep the stability of the entire system. The mismatch of the DCP molecules with the substrate lattice has also been observed in the experiment.展开更多
文摘Atomic force microscopy (AFM) was employed to quantitatively detect the interaction between a transcription factor, ZmDREBIA, and its target DNA sequence (DRE).The specificity of the interaction was revealed by comparing the binding probability of ZmDREBIA to DRE element with core sequence ACCGAC and to the ERE element with core sequence AGCCGCC. Moreover, the single-molecular unbinding force between ZmDREBIA and DRE element was determined using Poisson statistical method to be 99±9 pN.The results indicated that AFM could serve as a sensitive and reliable technique to probe the interaction properties of the transcription factor and DNA element at single-molecular level, thus indicating that AFM is advantageous over the traditional methods, such as the electrophoretic mobility shift assay, regarding to the functional analysis of transcription factors.
文摘The composite material of poly-(L-lactide) (PLLA) and carbon nanotubes (CNTs) were prepared. Itssurface morphologies and property were worked out by us-ing atomic force microscopy (AFM) and contact angle meas-urement. Moreover, the prime cytocompatibility was used to investigate the biocompatibility of the composite materialcontaining CNTs and the effects of CNTs on one aspect of cell function, cell affinity. The results obtained indicate that thecomposite material of PLLA and CNTs possesses good bio-compatibility for both the 3T3 fibroblasts and Oct-1 os-teoblast-like cells. The addition of CNTs will greatly affectcell affinity of the material, which may be disadvantage for the cell adhesion.
文摘Well-defined and controllable one-dimensional (1D) nanostructures of fullerene derivative have been pre- pared by an electrophoretic template synthesis method. The clusters of fullerene derivative formed in mixed solvents are introduced into the channels of porous alumina templates through a dc electric field. Four types of 1D nanostructures (solid nanowires, solid-wall nanotubes, porous nanowires and porous-wall nanotubes) have been obtained by changing the deposition parameters. This approach opens a new avenue to assemble fullerene derivatives, endohedral fullerenes, as well as other functional organic compounds, which can form clusters in 1D nanostructure arrays for applications in chemical sensors, light energy conversion devices and nano- scale electronic and optoelectronic devices.
基金supported by the National Natural Science Foundation of China(Grant Nos.20121301 and 20177025)the Chinese Academy of Sciences.
文摘The adsorption and assembling of bacterio-chlorophyll c (BChl c) on a highly oriented pyrolytic graphite (HOPG) surface have been investigated by the scanning tunneling microscopy (STM). BChl c molecules are found to self-organize a well-defined adlayer on HOPG surface with a monomeric structure different from the dimer association seen on adlayers of Chls a, c and BChlide c, d. A structural model is proposed for the adlayer.
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.20073053 and 20103008)the Foundation of the Chinese Academy of Sciences.
文摘An important precursor 4,5-didodecylthiolph- thalonitrile (DCP) for synthesis of phthalocyanines (Pcs) and subphthalocyanines (SubPcs) was synthesized and the as-sembling structure of this molecule on the basal plane of highly oriented pyrolytic graphite (HOPG) surface was characterized using the scanning tunneling microscopy (STM) in ambient conditions. In high-resolution images of the molecules, we found that the arrangement of the cyano groups forms a head-to-head configuration to keep the stability of the entire system. The mismatch of the DCP molecules with the substrate lattice has also been observed in the experiment.
