3 research outputs found
Nanoparticle-Aided Amplification of Fluorescence Polarization for Ultrasensitively Monitoring Activity of Telomerase
To
realize facile and reliable analyzing telomerase activity in
homogeneous, herein, for the first time, a fluorescent polarization
(FP) strategy was developed for polymerase chain reaction (PCR) free
monitoring activity of human telomerase at single-cell level ground
on gold nanoparticle (GNP) enhancement of FP. First, thiolated telomerase
substrate (TS) primer is modified to the surface of GNP via Au–S
bond. In the presence of telomerase, TS primer was extended via adding
hexamer repeats (GGGTTA), leading to the formation of a long elongation
DNA. Several short carboxyfluorescein (FAM)-modified complementary
DNA (F-cDNA) can hybridize with the hexamer repeats, resulting in
a sharp increase in FP value. Because of the GNP enhancement and self-amplification
of telomerase, telomerase activity accounting to one HeLa cell can
be rapidly detected in homogeneous solution. Telomerase activities
of various cell lines were also favorably estimated. Meanwhile, the
inhibition efficiency of telomerase inhibitor was studied, which holds
great potential in screening telomerase-targeted anticancer drugs
as well. So, a facile method was put forward to reliably and ultrasensitively
detect telomerase activity
Biomass-Swelling Assisted Synthesis of Hierarchical Porous Carbon Fibers for Supercapacitor Electrodes
The
preparation of porous materials from renewable energy sources is attracting
intensive attention due to in terms of the application/economic advantage,
and pore structural design is core in the development of efficient
supercapacitors or available porous media. In this work, we focused
on the transformation of natural biomass, such as cotton, into more
stable porous carbonaceous forms for energy storage in practical applications.
Biomorphic cotton fibers are pretreated under the effect of NaOH/urea
swelling on cellulose and are subsequently used as a biomass carbon
source to mold the porous microtubule structure through a certain
degree of calcining. As a merit of its favorable structural features,
the hierarchical porous carbon fibers exhibit an enhanced electric
double layer capacitance (221.7 F g<sup>–1</sup> at 0.3 A g<sup>–1</sup>) and excellent cycling stability (only 4.6% loss
was observed after 6000 cycles at 2 A g<sup>–1</sup>). A detailed
investigation displays that biomass-swelling behavior plays a significant
role, not only in improving the surface chemical characteristics of
biomorphic cotton fibers but also in facilitating the formation of
a hierarchical porous carbon fiber structure. In contrast to traditional
methods, nickel foams have been used as the collector for supercapacitor
that requiring no additional polymeric binders or carbon black as
support or conductive materials. Because of the absence of additive
materials, we can further enhance capacitance. This remarkable capacitive
performance can be due to sufficient void space within the porous
microstructure. By effectively increasing the contact area between
the carbon surface and the electrolyte, which can reduce the ion diffusion
pathway or buffer the volume change during cycling. This approach
opens a novel route to produce the abundantly different morphology
of porous biomass-based carbon materials and proposes a green alternative
method to meet sustainable development needs
Ordered Assembly of NiCo<sub>2</sub>O<sub>4</sub> Multiple Hierarchical Structures for High-Performance Pseudocapacitors
The
design and development of nanomaterials has become central
to the advancement of pseudocapacitive performance. Many one-dimensional
nanostructures (1D NSs), two-dimensional nanostructures (2D NSs),
and three-dimensional hierarchical structures (3D HSs) composed of
these building blocks have been synthesized as pseudocapacitive materials
via different methods. However, due to the unclear assembly mechanism
of these NSs, reports of HSs simultaneously assembled from two or
more types of NSs are rare. In this article, NiCo<sub>2</sub>O<sub>4</sub> multiple hierarchical structures (MHSs) composed of 1D nanowires
and 2D nanosheets are simply grown on Ni foam using an ordered two-step
hydrothermal synthesis followed by annealing processing. The low-dimensional
nanowire is found to hold priority in the growth order, rather than
the high-dimensional nanosheet, thus effectively promoting the integration
of these different NSs in the assembly of the NiCo<sub>2</sub>O<sub>4</sub> MHSs. With vast electroactive surface area and favorable
mesoporous architecture, the NiCo<sub>2</sub>O<sub>4</sub> MHSs exhibit
a high specific capacitance of up to 2623.3 F g<sup>–1</sup>, scaled to the active mass of the NiCo<sub>2</sub>O<sub>4</sub> sample
at a current density of 1 A g<sup>–1</sup>. A nearly constant
rate performance of 68% is achieved at a current density ranging from
1 to 40 A g<sup>–1</sup>, and the sample retains approximately
94% of its maximum capacitance even after 3000 continuous charge–discharge
cycles at a consistently high current density of 10 A g<sup>–1</sup>