Recyclable Functionalized Material for Sensitive Detection and Exceptional Sorption of Hexavalent Chromium and Permanganate Ions with Biosensing Applications

Abstract

Environmental remediation with a single platform for selective sensing and removal of toxic analytes with recyclability of the material has always been a desirable system for sustainability. However, materials comprising all the abovementioned advantages are rarely known for oxoanions. We herein developed a fluorogenic napthalimide-based functionalized mesoporous silica material (SiO2@NBDBIA) as a signaling and remediation system for oxoanions (CrO4 2–, Cr2O7 2–, and MnO4 –) from a pool of several anions. The fluorescence quenching of the SiO2@NBDBIA material in the presence of CrO4 2–, Cr2O7 2–, and MnO4 – ions gives the limit of detection (LOD) values of 6.23, 25.2, and 20.32 ppb, respectively, which are well below the maximum contaminant level demarcated by the United States Environmental Protection Agency. The maximum adsorption capacities of the material for the abovementioned oxoanions are found to be 352, 363, and 330 mg/g, respectively, which are well above those mentioned in the literature reports. Contrary to the literature-dominated irreversible ion-exchange mechanism, the reversible hydrogen-bonded binding of the material with the oxoanions leads to the recyclability of the material easily, which is very rare in the literature. The DFT calculations were performed to examine the interactions between the material and oxoanions. For real applications, this material was also used as a fluorescence probe to detect these oxoanions in the actual water samples, and more interestingly, used as a biosensing probe for these oxoanions in the living organism Artemia salina through fluorescence imaging. Thus, the SiO2@NBDBIA material is a unique example of recyclable material for detecting and remediating oxoanions.

Viologen-Based Cationic Metal–Organic Framework for Antibiotics Detection and MnO4– Removal in Water

“…In the first 3 h, 96% MnO 4 – in aqueous solution could be absorbed by Eu-CMOF (Figures b, S18, and S19). The adsorption capacity of MnO 4 – is calculated to be 1.1 g·g –1 (Figures c, S18, and S20) because of the open channel and decentralized distribution of the positive charges, which is relatively high compared with the recently reported materials. , The time-dependent MnO 4 – adsorption process could be well fitted by a pseudo-second-order kinetic equation (Figure d), indicating the adsorption of MnO 4 – is probably governed by chemisorption. , …”

“…− is calculated to be 1.1 g•g −1 (Figures 5c, S18, and S20) because of the open channel and decentralized distribution of the positive charges, which is relatively high compared with the recently reported materials. 48,49 The time-dependent MnO 4 − adsorption process could be well fitted by a pseudo-secondorder kinetic equation (Figure 5d), indicating the adsorption of MnO 4 − is probably governed by chemisorption. 49,50 In conclusion, a viologen derivative has been successfully utilized to construct a luminescent Eu-CMOF with a four-fold interpenetrating cationic diamondoid structure.…”

A TD-DFT study of a class of D–π–A fluorescent probes for detection of typical oxidants

“…23,24 Organic fluorescent probes, which are one of the major fluorescent sensing technologies, have been identified as the most promising on-site identification method due to their excellent simplicity, portability and inexpensiveness. [25][26][27][28][29][30] D-π-A molecule are textbook fluorescent probes for the detection of typical oxidants; these probes are generally constituted of a π-conjugated bridge connecting an electron-donating group (EDG) and electron-withdrawing group (EWG). [31][32][33] The electron deficiency of the π-conjugated bridge allows it to be feasibly attacked by the oxidant, and its cleavage interrupts the electron transfer between the EDG and EWG, eventually resulting in dramatic changes in the fluorescence excitation state.…”

Photoluminescence Quenching in Recyclable Water-Soluble Zn-Based Metal–Organic Framework Nanoflakes for Dichromate Sensing

“…Therefore, to effectively monitor and control Cr 2 O 7 2– in environmental media, it is urgent to develop a fast and convenient Cr 2 O 7 2– detection method. Currently, photoluminescence, − atomic absorption spectroscopy (AAS), chromatography, , inductively coupled plasma–mass spectrometry (ICP–MS), and electrochemical analysis are the most commonly used techniques for detecting Cr 2 O 7 2– . Considering the advantages of the simple operation, high sensitivity, and good selectivity of fluorescence spectroscopy, fluorescent probes are expected to be developed to provide an alternative method for the sensitive detection of Cr 2 O 7 2– in aqueous environments.…”