Akademik Veri Yönetim Sistemi
ACS OMEGA, 2026 (SCI-Expanded, Scopus)
Poly(diallyl dimethylammonium)/peroxotungstic acid nanoparticles (PDDA@PWA NPs) were successfully synthesized via electrostatic self-assembly between the cationic polyelectrolyte PDDA and the anionic PWA species. The morphology, architecture, and composition of the PDDA@PWA NPs were systematically characterized by using transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The newly developed, white composite exhibited excellent selectivity and adsorption capacity when used as a solid-phase extraction (SPE) platform for the efficient separation of trace Cr(VI) ions from aqueous matrices. A portable fiber-optic reflectance spectroscopy (FORS) analysis was subsequently performed directly on the Cr(VI)-PDDA@PWA surface employing the diphenyl carbazide (DPC) reagent. Meanwhile, the Cr(VI)-PDDA@PWA platform displayed a color change from yellow to red-violet for trace levels of Cr(VI) ions as low as 0.035 mu M. Under the optimized FORS conditions, a linear calibration curve was obtained for Cr(VI) concentrations ranging from 0.2 to 10 mu M, based on the measured reflectance intensity of the DPC-Cr(VI) complex. For comparative analysis and method validation, the colored DPC-Cr(VI) complex was eluted from the nanoparticle surface using an Liebermann-Burchard reagent@N,N-dimethylformamide (LBR@DMF) solution. The absorbance of Cr(VI) was proportional in a concentration range of 0.2-6.0 mu M with a detection limit of 0.01 mu M. The synthesized PDDA@PWA NPs displayed excellent FORS sensing performance for the sensitive, selective, and on-site detection of Cr(VI) ions. The proposed approach was employed for Cr(VI) detection in real samples, yielding satisfactory apparent recovery rates (93-97%).