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Sensor100
February 2016
NewTechnology Developed at University of Connecticut
Detects Organophosphates in Food
As pesticides or lethal chemical weapons, organophosphates (OPs) are deadly com-
pounds regardless of their intended target; they comprise 40 percent of the pesticides
used worldwide. The new sensor developed
by Profs. Lei and Hou utilizes a plant-based
esterase, or PLaE, which can be extracted
from wheat flour, soy, or corn. The new sen-
sor is a thoughtfully engineered matrix: Chi-
tosan, a plentiful compound derived from the
shells of crustaceans such as shrimp, acts like
a glue to hold the components of the sensor
together and also binds the sample, ensuring
everything is in close contact; Gold nanopar-
ticles are added to aid in electrical conductiv-
ity and electron transfer without interacting
with or altering the sample itself.; Graphene
nanosheets are included to ensure that com-
ponents are all interconnected, in order to increase conductivity and durability. Last but
not least, the matrix includes the plant-based esterase as the bio-recognition element
to interact with organophosphates. It is the enzyme activity change in the plant-based
esterase that is monitored by the sensor, and read using a meter.
University of Connecticut
Press Release23 February
A sensor that can detect toxic chemicals is
connected to a cable in the lab.
(Peter Morenus/UConn Photo)