Biology Reference
In-Depth Information
from platinum group, with the introduction of nanotechnology
and the increasing interest for biosensing applications, gold nano-
particles, due to their facile conjugation with biological molecules,
besides other advantages, are being shown to be the most used.
Their applications as either electrocatalytic labels or modifiers
of DNA related transducers are bringing important advantages
in terms of sensitivity and detection limits in addition to other
advantages.
Ag-NPs are not so commonly used as Au-NPs but nevertheless
their catalytic properties in electrochemical detection have also
been exploited. For instance, they were reported as promoters for
electron transfer between the graphite electrode and hemoglobin
in a NO sensor system where they also act as a base to attach the
hemoglobin onto a pyrolytic graphite electrode while preserving
the hemoglobin natural conformation and therefore its reactivity
[46]. With respect to the application of silver catalytic properties
on DNA hybridization detection, the published works refer mostly
to its use in combination with Au-NPs by means of chemical or
electrochemical silver deposition onto them [29].
The catalytic properties of nanoparticles used in protein detec-
tion can also be extended to DNA analysis. For example, the
selective electrocatalytic reduction of silver ions onto the surface of
Au-NP reported by our group and applied for protein detection
can be extended to DNA analysis too [47]. The hydrogen catalysis
reaction induced by Au-NPs [48] and applied even for cancer cells
detection [20] is expected to bring advantages for DNA detection as
well.
The reported studies suggest that the use of nanoparticles as
catalysts in electroanalysis in general, and particularly in DNA
sensingisnotconfinedto metal nanoparticlesonly.The conjugation
of nanoparticles with electrochemical sensing systems promises
large evolution in actual electroanalysis methods and is expected to
bring more advantages in DNA sensing overall in the development
of free PCR-DNA detection besides other applications that may
include microfluidics and lateral flow detection devices. These
worksareunderwayatourandotherlaboratories.Theirsuccessful
application in DNA detection in real samples would require a
significant improvement of cost-e
ciency of nanoparticle-based
