Professor Jinsung Park's research team has achieved a groundbreaking feat by successfully detecting the ultra-sensitive presence of perfluorooctanoic acid (PFOA) using self-assembled p-Phenylenediamine* nanoparticles (SAp-PD). This marks the first-ever application of SAp-PD nanoparticles for detecting PFOA, which is generated during the cooking process of Teflon-coated frying pans. The team's remarkable accomplishment was published in the esteemed international journal "Journal of Hazardous Materials," known for the top 3% in the field of environmental science.

*p-Phenylenediamine(p-PD) : It is an organic compound that is one of the ingredients in dyes, possessing an amino group (-NH2) at both ends. It typically exists as a white powder at room temperature, but it exhibits a characteristic reddish-brown color when oxidized in an aqueous solution.

PFOA, widely employed across various industries for its surfactant properties, heat resistance, and non-stick characteristics, has particularly found extensive use as a coating agent for cooking utensils such as frying pans. However, its classification as a Group 2B carcinogen by the International Agency for Research on Cancer (IARC), a subsidiary of the World Health Organization (WHO), has led to restrictions on its utilization. The detection of elevated levels of perfluorinated compounds in Daegu's tap water in 2018 further intensified the significance of detecting PFOA with high sensitivity.

The research team employed Raman spectroscopy, a technique that detects and analyzes unique spectral patterns produced when examining specific laser wavelengths on materials. Each substance possesses its distinct spectrum, analogous to individual fingerprints. To maximize the Raman signal, they incorporated the Surface Enhanced Raman Spectroscopy (SERS) method, which relies on the nanostructure of the substrate to enhance the analysis. In this study, the team utilized a silver nanograss substrate, on which they measured the variation in Raman intensity of SAp-PD—exhibiting its own distinct Raman spectrum—before and after exposure to PFOA.

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In a significant scientific breakthrough, research team have developed an ultra-sensitive detection sensor technology for perfluorooctanoic acid (PFOA) by harnessing the unique properties of p-Phenylenediamine (p-PD). When p-PD is present in an aqueous solution, it gradually undergoes oxidation over time, transforming into self-assembled spherical nanoparticles while exhibiting distinct Raman spectra. However, when p-PD interacts with PFOA, the nanostructure undergoes collapse, leading to a reduction in Raman spectrum intensity. Leveraging this mechanism, the team successfully developed a pioneering technology for detecting PFOA with exceptional sensitivity, marking a significant advancement in the field.

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The research team achieved the detection of PFOA in distilled water at an astonishingly low concentration of 1.28 pM (pico molar, 10^-12 M) using SAp-PD nanoparticles. In real environmental, they detected PFOA at a concentration of 1.6 nM (nano molar, 10^-9 M) in tap water. Impressively, they also succeeded in detecting PFOA concentrations of 1.69 nM and 10.3 μM (micro molar, 10^-6 M) when examining Teflon-coated frying pans scratched with an iron scourer and freshly cooked rice in the same pan, respectively.

Professor Jinsung Park expressed his optimism about the potential applications of this technology, stating, "The proposed technology holds significant promise not only for detecting perfluorinated compounds but also for identifying various environmentally toxic substances." He emphasized the prospects of applying the developed technology in future environmental monitoring efforts.

Hyunjun Park, the doctoral candidate involved in the research, shared his aspirations, saying, "Building upon this study, I hope to establish a versatile multi-sensing platform capable of highly sensitive detection of toxic substances that pose risks to human health in real environmental."

The research was conducted with the support by the Environmental Pollution Management Technology Development Project by the Korea Environmental Industry & Technology Institute and received funding from the Basic Science Research and Mid-career Research Programs of the National Research.

Meanwhile, Professor Jinsung Park has been making significant strides in the field of detecting toxic substances in disease-inducing environments. Notably, he recently published his research achievements on the development of a sensor for detecting heavy metals in wastewater in the renowned international academic journal ACS Sustainable Chemistry & Engineering (IF: 9.224) on April 21. This publication further demonstrates Professor Park's dedication to advancing research on the identification of toxic substances linked to the onset of various diseases.

※ Paper: Ultra-sensitive SERS detection of perfluorooctanoic acid based on self-assembled p-phenylenediamine nanoparticle complex

※ Journal: Journal of Hazardous Materials, IF: 14.224 

※ https://www.sciencedirect.com/science/article/abs/pii/S0304389423006672?via%3Dihub