Pukyong National University Student Develops Highly Sensitive Colorimetric Sensor for Detecting Environmental Toxic Substances

Sungman Lee, PhD Candidate in Chemistry,
Publishes in the International Journal 'Sensors and Actuators B: Chemical'

Pukyong National University (President: Bae Sanghoon) announced on May 8 that a study by Sungman Lee, a PhD candidate in the Department of Chemistry, on the development of a colorimetric on-site detection sensor was recently published in a world-class international journal in the field of instrumentation and measurement (JCR top 0.7%).

This research, a collaborative achievement by lead author Sungman Lee (PhD candidate), Professor Songyi Lee (Department of Chemistry), and Professor Jungho Shin (Department of Biomedical Engineering), resulted in the development of a highly sensitive colorimetric sensor system capable of rapidly and accurately detecting the highly toxic environmental pollutant cyanide (CN) with the naked eye.

Research team. (From left: Sungman Lee, PhD candidate; Songyi Lee, Professor; Jungho Shin, Professor) Provided by Pukyong National University

The research team successfully designed a new PDA-BMN sensor by integrating a receptor that selectively recognizes cyanide into a polydiacetylene (PDA)-based polymer system. When cyanide is present, the π-conjugated backbone of the molecule twists, causing a distinct color change from blue to orange.

This sensor achieved a low detection limit of 0.55 μM, allowing it to detect cyanide at concentrations lower than the World Health Organization (WHO) guideline for cyanide in drinking water (1.9 μM).

Notably, this study expanded the platform by mounting the sensor onto a paper-based lateral flow assay (LFA) strip, enabling immediate on-site detection of toxic substances without the need for expensive equipment. The research team also introduced a 'partial press' technique to control the fluid flow rate in the LFA strip, significantly enhancing detection sensitivity as a technical advancement.

Professor Songyi Lee stated, "This achievement, which combines highly sensitive molecular sensors with portable diagnostic platforms through the collaboration of basic science and engineering, is expected to mark a significant turning point in the fields of smart environmental sensors and on-site diagnostics. We will continue to pursue convergence research that meets both practical and academic needs."

This research was supported by the G-LAMP (Learning & Academic research institution for Master's, PhD students, and Postdocs) project at Pukyong National University and is attracting attention as a next-generation analytical technology that enables easy and accurate on-site diagnostics in the field of environmental monitoring.