An optical monitoring device combining a smartphone with
a polychromatic
ratiometric fluorescence-colorimetric paper sensor was developed to
detect Hg2+ and S2– in water and seafood.
This monitoring included the detection of food deterioration and was
made possible by processing the sensing data with a machine learning
algorithm. The polychromatic fluorescence sensor was composed of blue
fluorescent carbon quantum dots (CDs) (BU-CDs) and green and red fluorescent
CdZnTe quantum dots (QDs) (named GN-QDs and RD-QDs, respectively).
The experimental results and density functional theory (DFT) prove
that the incorporation of Zn can improve the stability and quantum
yield of CdZnTe QDs. According to the dynamic and static quenching
mechanisms, GN-QDs and RD-QDs were quenched by Hg2+ and
sulfide, respectively, but BU-CDs were not sensitive to them. The
system colors change from green to red to blue as the concentration
of the two detectors rises, and the limits of detection (LOD) were
0.002 and 1.488 μM, respectively. Meanwhile, the probe was combined
with the hydrogel to construct a visual sensing intelligent test strip,
which realized the monitoring of food freshness. In addition, a smartphone
device assisted by multiple machine learning methods was used to text
Hg2+ and sulfide in real samples. It can be concluded that
the fabulous stability, sensitivity, and practicality exhibited by
this sensing mechanism give it unlimited potential for assessing the
contents of toxic and hazardous substances Hg2+ and sulfide.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.