This study investigates the influence of positional isomerism on the physicochemical characteristics of polymeric matrices by examining polyo-anisidine (POA) and polyp-anisidine (PPA) in conjunction with TiO₂ nanoparticles. The synthesis of POA@TiO₂ and PPA@TiO₂ involved chemical oxidative polymerization. X-ray diffraction analysis revealed the anatase structure of TiO₂ nanoparticles. Transmission electron microscopy confirmed the successful integration of TiO₂ nanoparticles within the polymer matrix. Moreover, FTIR and UV–Vis spectroscopy confirmed the effective interaction between the nanoparticle and the polymer. TGA indicated that POA@TiO₂ exhibited a lower weight loss than PPA@TiO₂, suggesting an enhancement in thermal stability. Although the incorporation of TiO₂ nanoparticles led to a reduction in the electrical conductivity of the pristine polymers (PPA and POA), the resultant nanocomposites retained high conductivities within the range of 0.08 to 0.34 S.cm⁻¹. Furthermore, the POA-based polymer matrix displayed promising electrochemical properties. Significantly, the adherence of the POA layer to TiO₂ nanoparticles suggests potential practical applications.

The chemical industry explosion in the 20th century has led to increased environmental pollution, affecting fauna, flora, and waterways. These substances alter water’s taste, color, and smell, making it unfit for consumption or toxic. Agricultural water networks face threats from pollution before and after treatment. Some chemical contaminants, like pesticides, are embedded in natural biogeochemical cycles. In this study, we developed a simple and low-cost procedure for the fabrication of needles coated with polydimethylsiloxane (PDMS) as an efficient sorbent for the microextraction of organic pollutant traces from water. The prepared needles were used as an alternative for commercial solid-phase micro-extraction (SPME) devices in analytical chemistry. The PDMS polymeric phase was characterized by Fourier-transform infrared spectroscopy (FT-IR), thermogravimetry (TGA), and scanning electron microscopy (SEM). The PDMS-coated needles were used for extraction of thirteen pesticides by direct-immersion solid-phase microextraction (DI-SPME) from contaminated waters, followed by determination with gas chromatography-mass spectrometry (GC-MS). The developed analytical method showed limits of detection (LODs) between 0.3 and 2.5 ng mL⁻¹ and RSDs in the range of 0.8–12.2%. The homemade needles were applied for the extraction of pesticides in surface and ground aqueous samples collected from an agricultural area. Several target pesticides were identified and quantified in the investigated water samples.