Focus on quantum dots as potential fluorescent probes for monitoring food toxicants and foodborne pathogens

Water-soluble quantum dots (QDs) are fluorescent
semiconductor nanoparticles with narrow, very specific, stable
emission spectra. Therefore, the bioconjugation of these QDs
for biological fluorescent labeling may be of interest due to
their unique physical and optical properties as compared to
organic fluorescent dyes. These intrinsic properties of QDs
have been used for the sensitive detection of target analytes.
From the viewpoint of ensuring food safety, there is a need to
develop rapid, sensitive and specific detection techniques to
monitor food toxicants in food and environmental samples.
Even trace levels of these toxicants can inadvertently enter the
food chain, creating severe health hazards. The present review
emphasizes the application of water-soluble bioconjugated
QDs for the detection of food contaminants such as pesticides,
pathogenic bacterial toxins such as botulinum toxin, enterotoxins
produced by Staphylococcus aureus, Escherichia coli,
and for the development of oligonucleotide-based microarrays.
This review also emphasizes the application of a
possible resonance energy transfer phenomenon resulting
from nanobiomolecular interactions obtained through the
bioconjugation of QDs with biomolecules. Furthermore, the
utilization of significant changes in the spectral behavior of
QDs (attributed to resonance energy transfer in the bioconjugate)
in future nanobiosensor development is also emphasized.