Nanoparticles for Trace Analysis of Toxins: Present and Future Scenario - Advanced Materials for Agriculture, Food and Environmental Safety - page 192

an application for food analysis has been, up to now, unexploited. Goldman
et al. [69] have used QDs for l uoroimmuno assays of toxins. h ey detected
four toxins simultaneously, three of which are naturally responsible for
food or waterborne sickness. h e CdSe-ZnS core-shell QDs were capped
with dihydrolipoic acid and bioconjugates with the appropriate antibod-
ies were prepared. A sandwich immunoassay was performed in microti-
tre plates, where the toxins and dif erent QDs were incubated for an hour.
Fluorescence was measured at adequate wavelengths and, although there
was spectral overlap, deconvolution of spectra revealed the l uorescence
contribution of all toxins. Signals increased with toxin concentration in
dif erent ranges according to the particular toxin. No LODs were reported.
Although the authors treated the bioconjugate QDs as l uororeagents, they
can be considered as “chemosensing devices.” An ultrasensitive densi-
tometry method was used for the detection of cytokines by nanoparticle-
modii ed aptamers [70, 71]. Gold nanoparticles were also employed for an
immunoassay for the detection of al atoxin B1 (AFB1) in foods [72].

7.7 Conclusion

Decontamination is the reduction or removal of chemical and biological
agents by means of physical means or chemical neutralization or detoxi-
i cation techniques. Nanotechnology has shown huge potential in areas
as diverse as drug development, water decontamination, information and
communication technologies, and the production of stronger, lighter mate-
rials and human health care. Water and air are two vital components of life
on earth; the existence of life on earth is made possible largely because of
their importance to metabolic processes within the body. Clean and fresh
water and air are essential for the existence of life. h e recent developments
in nanotechnology have raised the possibility of environmental decontam-
ination through several nanomaterials, processes and tools. h is chapter
summarizes the expertise that various decontamination approaches can
bring to the successful realization of environmental remediation.

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