- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Colorimetric and turn-on Fluorescence Chemosensor for Hg2+ Ion Detection in Aqueous Media
摘要： A new rhodamine 6G based fluorescent and colorimetric chemosensor, containing N-methyl imidazole nucleus, for the selective detection of Hg2+ ion was designed and synthesized. The results of UV-Vis and fluorescence spectral study indicated that the receptor is selective and sensitive towards Hg2+ with no noticeable interference with other competitive metal ions. The addition of Hg2+ to the receptor induced a rapid color change to pink from colorless and the turn-on fluorescence response toward Hg2+ among different cations was studied. The stoichiometric ratio of 1:1 between the receptor and Hg2+ was supported by Job’s plot. The color change and turn-on fluorescence response upon addition of Hg2+ ion was ascribed by the spirolactam ring-opening mechanism. The probable mode of binding between the receptor and Hg2+ was confirmed by 1H NMR and Mass spectral study. For the practical application, its electrospun nanofiber test strips successfully applied to recognize Hg2+ ion in aqueous media.
关键词： Sensing,Mercury ion,Nanofiber,Fluorescent
更新于2025-09-23 15:23:52
-
Novel Multifunctional Luminescent Electrospun Fluorescent Nanofiber Chemosensor-Filters and Their Versatile Sensing of pH, Temperature, and Metal Ions
摘要： Novel multifunctional ?uorescent chemosensors composed of electrospun (ES) nano?bers with high sensitivity toward pH, mercury ions (Hg2+), and temperature were prepared from poly(N-Isopropylacrylamide-co-N-methylolacrylamide-co-rhodamine derivative) (poly(NIPAAm-co-NMA-co-RhBN2AM)) by employing an electrospinning process. NIPAAm and NMA moieties provide hydrophilic and thermo-responsive properties (absorption of Hg2+ in aqueous solutions), and chemical cross-linking sites (stabilization of the ?brous structure in aqueous solutions), respectively. The ?uorescent probe, RhBN2AM is highly sensitive toward pH and Hg2+. The synthesis of poly(NIPAAm-co-NMA-co-RhBN2AM) with different compositions was carried on via free-radical polymerization. ES nano?bers prepared from sensory copolymers with a 71.1:28.4:0.5 NIPAAm:NMA:RhBN2AM ratio (P3 ES nano?bers) exhibited signi?cant color change from non-?uorescent to red ?uorescence while sensing pH (the λPL, max exhibited a 4.8-fold enhancement) or Hg2+ (at a constant Hg2+ concentration (10?3 M), the λPL, max of P3-?bers exhibited 4.7-fold enhancement), and high reversibility of on/off switchable ?uorescence emission at least ?ve times when Hg2+ and ethylenediaminetetraacetic acid (EDTA) were sequentially added. The P3 ES nano?brous membranes had a higher surface-to-volume ratio to enhance their performance than did the corresponding thin ?lms. In addition, the ?uorescence emission of P3 ES nano?brous membranes exhibited second enhancement above the lower critical solution temperature. Thus, the ES nano?brous membranes prepared from P3 with on/off switchable capacity and thermo-responsive characteristics can be used as a multifunctional sensory device for speci?c heavy transition metal (HTM) in aqueous solutions.
关键词： thermo-response,chemosensor,electrospun nano?bers,pH,mercury ion
更新于2025-09-09 09:28:46