3 research outputs found
Synchronized Assembly of Gold Nanoparticles Driven by a Dynamic DNA-Fueled Molecular Machine
A strategy for gold nanoparticle (AuNP) assembly driven
by a dynamic
DNA-fueled molecular machine is revealed here. In this machine, the
aggregation of DNA-functionalized AuNPs is regulated by a series of
toehold-mediated strand displacement reactions of DNA. The aggregation
rate of the AuNPs can be regulated by controlling the amount of oligonucleotide
catalyst. The versatility of the dynamic DNA-fueled molecular machine
in the construction of two-component “OR” and “AND”
logic gates has been demonstrated. This newly established strategy
may find broad potential applications in terms of building up an “interface”
that allows the combination of the strand displacement-based characteristic
of DNA with the distinct assembly properties of inorganic nanoparticles,
ultimately leading to the fabrication of a wide range of complex multicomponent
devices and architectures
Integrating DNA-Strand-Displacement Circuitry with Self-Assembly of Spherical Nucleic Acids
Programmable
and algorithmic behaviors of DNA molecules allow one
to control the structures of DNA-assembled materials with nanometer
precision and to construct complex networks with digital and analog
behaviors. Here we developed a way of integrating a DNA-strand-displacement
circuit with self-assembly of spherical nucleic acids, wherein a single
DNA strand was used to initiate and catalyze the operation of upstream
circuits to release a single strand that subsequently triggers self-assembly
of spherical nucleic acids in downstream circuits, realizing a programmable
kinetic control of self-assembly of spherical nucleic acids. Through
utilizing this method, single-nucleotide polymorphisms or indels occurring
at different positions of a sequence of oligonucleotide were unambiguously
discriminated. We provide here a sophisticated way of combining the
DNA-strand-displacement-based characteristic of DNA with the distinct
assembly properties of inorganic nanoparticles, which may find broad
potential applications in the fabrication of a wide range of complex
multicomponent devices and architectures
What Controls the “Off/On Switch” in the Toehold-Mediated Strand Displacement Reaction on DNA Conjugated Gold Nanoparticles?
In DNA dynamic nanotechnology, a
toehold-mediated DNA strand-displacement
reaction has demonstrated its capability in building complex autonomous
system. In most cases, the reaction is performed in pure DNA solution
that is essentially a one-phase system. In the present work, we systematically
investigated the reaction in a heterogeneous media, in which the strand
that implements a displacing action is conjugated on gold nanoparticles.
By monitoring the kinetics of spherical nucleic acid (SNA) assembly
driven by toehold-mediated strand displacement reaction, we observed
significant differences, i.e., the abrupt jump in behavior of an “off/on
switch”, in the reaction rate when the invading toehold was
extended to eight bases from seven bases. These phenomena are attributed
to the effect of steric hindrance arising from the high density of
invading strand conjugated to AuNPs. Based on these studies, an INHIBIT
logic gate presenting good selectivity was developed