Development
of an easy-to-use, low-cost, household device can help
the consumer quickly identify an organophosphorus (OP) residue concentration
level. In this work, we demonstrate a 3D-printed, portable, fluorescent-sensing
platform for smartphone-capable detection of OPs in vegetables. For
development of the proposed device, we utilize the smartphone for
capturing the strong thiol-activated fluorescence, which was produced
by hydrolysis of OPs in the presence of alkali. The thiol-responsive
AIEgen (maleimide-functionalized tetraphenylethylene) was non-emissive
in both solution and the solid state but could be readily lighted
up by the click addition of thiol to its MI pendant. An android application
“Detection” has been developed on the basis of the gray
value to analyze the different concentration levels of OPs in vegetable
samples. The gray value was linearly related with the concentration
of five kinds of organophosphorus residue, ranging from 0 to 20 μg/mL.
It was also applied for determination of OPs residue in the leaves
of cowpea, celery, and Chinese cabbage. Different from acetylcholinesterase
enzyme-based sensors for poor stability under high temperature, the
proposed method was a direct detection method for OPs and can be used
for rapid monitoring of OPs residue concentration levels before LC-MS
analysis.