Polyvinylpyrrolidone as a New Fluorescent Sensor for Nitrate Ion

Abstract

In this study, non-conjugated polyvinylpyrrolidone(PVP) was investigated for the first time as the potential polymeric material to sense nitrate ions by fluorescence spectroscopy. The PVP was diluted into various concentrations (3-10%) and they were used to sense the nitrate ions in different concentrations (0.1-100 mM). The PVP showed two excitation peaks at 285 and 330 nm due to the presence of C=O and N-C groups, respectively. One strong emission at 400 or 408 nm was observed with the excitation at 285 or 330 nm. The higher value of quenching constant at excitation wavelength of 285 nm indicated that C=O site was more favored for NO 3 -ions sensing than the N-C site. The PVP 7% gave the highest quenching constant; where the K SV value was 9.89 × 10 -3 mM -1 and 2.44 × 10 -3 mM -1 for excitation at 285 and 330 nm, respectively. The sensing capability was evaluated in the presence of interference ions (SO 4 2-, HCO 3 -, Cl -, and OH -). It was observed that the interference ions interacted strongly with the C=O, but weakly with the N-C. Therefore, in the presence of the interference ions, the PVP would be a potential fluorescent sensor when it is excited at 330 nm.Keywords: polyvinylpyrrolidone; fluorescent sensor; nitrate ions; quenching Abstrak Dalam kajian ini, polivinilpirolidon (PVP) yang bersifat bukan konjugat dikaji untuk kali pertama sebagai bahan polimer yang berpotensi untuk mengesan ion nitrat dengan spektroskopi pendaflour. PVP dicairkan kepada kepekatan yang berlainan (3-10%) dan digunakan untuk mengesan ion nitrat dalam kepekatan yang berbeza (0.1-100 mM). PVP menunjukkan dua puncak pengujaan pada 285 and 330 nm dengan kewujudan C=O dan N-C masing-masing. Satu puncak pemancaran yang tinggi pada 400 atau 408 nm diperolehi dengan pengujaan pada 285 atau 330 nm. Pemalar pelidap kejutan dengan nilai yang lebih tinggi pada puncak pengujaan 285 nm menunjukkan bahawa tapak C=O lebih cenderung untuk mengesan ion NO 3 -daripada tapak N-C. PVP 7% memberi pemalar pelidap kejutan yang paling tinggi, dengan nilai K SV 9.89 × 10 -3 mM -1 and 2.44 × 10 -3 mM -1 untuk puncak pengujaan pada 285 dan 330 nm masing-masing. Kemampuan pengesanan dinilai dengan kehadiran ion gangguan (SO 4 2-, HCO 3 -, OH -, and Cl -). Hasil kajian menunjukkan bahawa ion gangguan berinteraksi kuat dengan C=O, tetapi lemah dengan N-C. Oleh itu, dengan kehadiran ion gangguan, PVP berpotensi menjadi pendafluor sensor pada tapak pengujaan 330 nm.Kata kunci: polivinilpirolidon; pengesan pendaflour, ion nitrat, pelidap kejutan

Optical and Dielectric Features of PVA/CMC/PVP/ZnMn2O4/CuCo2O4/x wt% MWCNTs Blended Polymers for Optoelectronic Applications

“…53 PVP displayed a blue color which associated with the π*→π band transition in PVP molecules, 54 while the presence of C=O and N-C groups in PVP was thought to be responsible for the UV color. 55 The green color may be caused by the vacancy and/or interstitial states in the structure via self-activated centers. 56 The colors released by different samples have also been described using color coordinates derived from the CIE 1931 chromaticity diagram (Fig.…”

Insights into the Mechanism of Tryptophan Fluorescence Quenching due to Synthetic Crowding Agents: A Combined Experimental and Computational Study

“…The enormous reduction in fluorescence intensity of Trp in the presence of PVP 40 (Figure ) could be due to the fact that the absorption wavelength of PVP 40 ranges from 230 to 400 nm. The PVP 40 exhibits two excitation peaks due to the presence of CO and NC groups at 285 and 330 nm, respectively . Therefore, energy transfer may be taking place from the excited Trp to PVP 40, causing a significant decrease in the emission intensity of Trp.…”

“…The PVP 40 exhibits two excitation peaks due to the presence of C=O and N≡C groups at 285 and 330 nm, respectively. 50 Therefore, energy transfer may be taking place from the excited Trp to PVP 40, causing a significant decrease in the emission intensity of Trp. Other mechanisms such as sphere-of-action quenching (vide infra) 34 and self-aggregation of Trp molecules in the presence of PVP 40 could also cause such a drastic reduction in fluorescence intensity.…”

Correlation of ZnO Surface Morphology and Sensing Performance of EGFET Nitrate Sensor

“…Polyvinyl pyrrolidone (PVP) has several advantages in terms of flexibility, environmental stability, non-toxic and biodegradable. Tang et al [24] have reported their work on nitrate detection using PVP based on a fluorescent sensor. From their research, its shows that the PVP polymer can detect nitrate ions.…”