A sensor array for the discrimination of polycyclic aromatic hydrocarbons using conjugated polymers and the inner...

Area of Science:

• Environmental Chemistry
• Analytical Chemistry
• Materials Science

Background:

• Polycyclic aromatic hydrocarbons (PAHs) are persistent pollutants from natural and human activities, posing risks to health and the environment.
• Detecting and distinguishing PAHs is challenging due to their similar structures and complex mixtures.
• Existing methods struggle with the rapid and reliable identification of these compounds.

Purpose of the Study:

• To develop a straightforward method for the quantitative and qualitative profiling of polycyclic aromatic hydrocarbons (PAHs).
• To utilize the inner filter effect (IFE) with conjugated polymer (CP) arrays for PAH detection and discrimination.
• To create a sensor array capable of identifying specific PAHs within complex mixtures.

Main Methods:

• Constructed a sensor array using six fluorescent fluorene-based copolymers with 2-phenylbenzimidazole substituents.
• Leveraged the inner filter effect (IFE) where spectral overlap between copolymers and PAHs modulates fluorescence.
• Employed multivariate analysis, including linear discriminant analysis (LDA) and principal component analysis (PCA), for data interpretation.

Main Results:

• The CP array demonstrated a pronounced inner filter effect (IFE) with PAHs, enabling detection.
• Distinct spectral signatures, or "chemical fingerprints," were generated for each PAH due to subtle copolymer structural differences.
• The sensor array successfully discriminated between 16 priority pollutant PAHs using LDA and PCA.

Conclusions:

• The developed sensor array offers a novel approach for the detection and discrimination of PAHs.
• This is the first multivariate system utilizing IFE-modulated CP spectral signatures for analyzing closely related polynuclear aromatic species.
• The method provides a promising tool for environmental monitoring and risk assessment of PAH contamination.