Electrochromic Molecular Imprinting Sensor for Visual and Smartphone-Based Detections.

Area of Science:

• Electrochemistry
• Materials Science
• Sensor Technology

Background:

• Molecularly imprinted technology provides robust molecular recognition elements with high selectivity.
• Electrochromic materials offer a visual readout for sensing applications.
• Iridium oxide nanoparticles (IrOx NPs) function as effective physicochemical transducers.

Purpose of the Study:

• To develop a sensitive and selective electrochromic sensor for detecting the pesticide chlorpyrifos.
• To integrate molecularly imprinted polymers (MIPs) with IrOx NPs for enhanced detection capabilities.
• To establish a rapid and visually interpretable sensing platform using electrochromism.

Main Methods:

• Fabrication of the sensor using screen-printing technology on indium tin oxide electrodes.
• Electrodeposition of IrOx NPs followed by thermal polymerization of polypyrrole in the presence of chlorpyrifos.
• Detection via direct visual color change upon applying oxidation potentials and smartphone imaging analysis.

Main Results:

• The sensor demonstrated a direct correlation between applied potential and color change, indicating analyte concentration.
• Smartphone imaging quantified chlorpyrifos concentration based on color intensity.
• Achieved a wide dynamic range of 100 fM to 1 mM for chlorpyrifos detection.

Conclusions:

• This study presents the first electrochromic MIP sensor utilizing IrOx NPs for selective and sensitive analyte detection.
• The developed sensor offers a promising platform for the rapid and visual detection of toxic compounds like chlorpyrifos.
• The combination of electrochromism and molecular imprinting provides a powerful approach for advanced chemical sensing.