Na–Ln Heterometallic Coordination Polymers: Structure Modulation by Na⁺ Concentration and Efficient Detection to Tetracycline Antibiotics and 4-(Phenylazo)aniline

Abstract

On the basis of the lanthanide metalloligand [Ln­(ODA)3]3– (H2ODA = oxydiacetic acid), three new Na–Ln heterometallic coordination polymers, [Ln­(ODA)3Na2] n [Ln = Eu (1) and Gd (2)] and [Tb­(ODA)3Na3(H2O)2] n (3), had been assembled by adjusting the concentration of Na+ ions in the reaction system. The investigations of fluorescence sensing showed that 1 could be a ratiometric probe to detect tetracycline (TC) and oxytetracycline (OTC) with high sensitivity and low detection limits, 71.92 ppb for the former and 45.54 ppb for the latter, and 3 could selectively sense 4-(phenylazo)­aniline through the turn-off pathway with 14.59 ppb of detection limits. Moreover, the competing and circulating experiments indicated that both 1 and 3 had satisfactory antiinterference and recyclability for the corresponding analytes. All of these results implied that 1 and 3 should be potential fluorescent sensors for the detection of TC/OTC and 4-(phenylazo)­aniline, and the possible sensing mechanism had also been discussed in depth.

Two Multiresponsive Luminescent Zn-MOFs for the Detection of Different Chemicals in Simulated Urine and Antibiotics/Cations/Anions in Aqueous Media

“…Luminescent metal–organic frameworks (LMOFs) have the advantages of high specific surface areas, adjustable structures, and luminescence properties. They are considered as potential sensor materials for detecting a variety of substances, including metal ions, anions, organic explosives, antibiotics, amino acids, and biomolecules. − The analyte-dependent luminescence changes of these MOFs could be detected by a mechanism which relies on various photoinduced electron-transfer (PET) processes. Structurally, most of them are assembled from conjugated aromatic organic ligands with different potential functional sites.…”

Stable Zinc(II) Coordination Polymer as a Rapid and Highly Sensitive Fluorescence Sensor for the Discriminative Sensing of Biomarker 2-(2-Methoxyethoxy) Acetic Acid

“…Contrary to the emission spectra, the excitation spectra of LCP 1 and the UV absorption spectra of MEAA had a large overlap area (Figure S12), which showed the competitive absorption between LCP 1 and MEAA. The competitive absorption will affect the energy transfer from 4-dptb to Zn 2+ ions, thus possibly resulting in competition quenching . Furthermore, the overlap between the UV absorption spectra of LCP 1 and MEAA also proved the competitive absorption mechanism (Figure S13).…”

“…The competitive absorption will affect the energy transfer from 4-dptb to Zn 2+ ions, thus possibly resulting in competition quenching. 47 Furthermore, the overlap between the UV absorption spectra of LCP 1 and MEAA also proved the competitive absorption mechanism (Figure S13).…”

A New Covalent Organic Framework of Dicyandiamide-Benzaldehyde Nanocatalytic Amplification SERS/RRS Aptamer Assay for Ultratrace Oxytetracycline with the Nanogold Indicator Reaction of Polyethylene Glycol 600

“…Therefore, it is urgent to establish new analytical methods for tracing OTC besides classical methods such as chromatography. Ma et al established a fluorescent Na-Ln heterometallic CP as a fluorescent probe for the quantitative detection of OTC [17]. The linear range was 0-100 µmol/L, and the detection limit was 0.09 µmol/L.…”