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The color-rendering abilities of esterified natural dyes are influenced by the structure of their parent dyes and the position at which the ester group is introduced, resulting in low efficiency in screening and synthesizing suitable esterified natural dyes for dyeing natural fibers with supercritical carbon dioxide. In this study, density functional theory was used to quickly screen the parent natural dyes and esterification position of natural dyes. The findings indicated that B3LYP/def2-TZVP level and CAM-B3LYP (ω = 0.01)/def2-TZVP level yield the most accurate UV–vis absorption spectra calculations for natural dyes and their esterified derivatives, as evidenced by the smallest error compared to experimental values. The rutin, the carminic acid, and the icariin as the parent dyes were more suitable for esterification, and the introduction of ester groups solely on the glycosides of these dyes had negligible impact on their color-rendering abilities. Furthermore, considering the influence of ester groups on natural dye solubility, it was observed that the dyeing properties of glycoside esterified products derived from rutin, carminic acid, and icariin were better than those of their parent dyes, rendering them more appropriate for dyeing natural fibers in supercritical carbon dioxide. [ABSTRACT FROM AUTHOR]

The construction and investigation of dual-functional coordination polymers (CPs) with proton conduction and luminescence sensing is of great significance in clean energy and agricultural monitoring fields. In this work, an Mn-based coordination polymer (Mn-CP), namely, [Mn0.5(HL)] (H2L = HOOCC6H4C6H4CH2PO(OH)OCH3), was hydrothermally synthesized. Mn-CP has a one-dimensional (1D) chain structure, in which uncoordinated –COOH groups can serve as potential sites for fluorescence sensing. Moreover, Mn-CP shows good water and pH stabilities, offering the feasibility for proton conduction and sensing applications. Mn-CP displays comparatively high proton conductivity of 1.07 × 10−4 S cm−1 at 368 K and 95% relative humidity (RH), which is promising for proton conduction materials. Moreover, it can serve as a repeatable, highly selective, and visualized fluorescence sensor for detecting oxytetracycline (OTC). More importantly, Mn-CP reveals an amazing quantitative sensing of OTC in actual samples such as seawater, aquaculture freshwater, soil infiltration solutions, and tap water. This work proves the excellent application potential of dual-functional CPs in the field of clean energy and environmental protection, especially for the fluorescence detection of antibiotics in aquaculture systems. [ABSTRACT FROM AUTHOR]

By selecting a bisphosphonic ligand H4L (H4L = 4-F-C6H4CH2N(CH2PO3H2)2) and a coligand oxalate (H2C2O4), three isostructural lanthanide metal–organic frameworks (Ln-MOFs) with a 2D layer structure, [Ln(H3L)(C2O4)]·2H2O (Ln = Eu (1), Gd (2), or Tb (3)), were hydrothermally prepared. By tuning the molar ratio of Eu3+, Gd3+, and Tb3+ in the above reactions, six bimetallic or trimetallic doped Ln-MOFs (EuxTb1−x (x = 0.02 (4), 0.04 (5), and 0.06 (6)), Gd0.94Eu0.06 (7), Gd0.96Tb0.04 (8) and Gd0.95Tb0.03Eu0.02 (9)) were obtained. The powder X-ray diffraction (PXRD) patterns of doped Ln-MOFs 4–9 show that they are isomorphous with 1–3. The bimetallic doped Ln-MOFs show a gradual variation of luminous colors between yellow-green, yellow, orange, pink, and light blue. Meanwhile, the trimetallic doped Gd0.95Tb0.03Eu0.02 Ln-MOF (9) displays near white-light emission with a quantum yield of 11.39%. Interestingly, the luminous inks of 1–9 are invisible and color tunable, which makes it possible to promote their anti-counterfeiting applications. Additionally, 3 displays good thermal, water, and pH stabilities, which provides the feasibility for its sensing application. The luminescence sensing experiments show that 3 can serve as a highly selective, reusable, and ratiometric luminescent sensor of sulfamethazine (SMZ). Moreover, 3 shows an excellent SMZ detection performance in real samples, such as mariculture water and real urine. Owing to the visible variation of the response signal under a UV lamp, portable SMZ test paper was prepared. [ABSTRACT FROM AUTHOR]

Developing high-accuracy luminescent sensors for detecting emerging environmental pollutants is of great importance and is still a challenge. Utilizing a 4-carboxyphenylphosphonic acid (H3pbc) ligand, a novel one-dimensional (1D) Zn-based coordination polymer with the formula [Zn2(Hpbc)2(2,2′-bipy)(H2O)]·H2O (Zn–CP, H3pbc = 4-HOOCC6H4PO3H2, 2,2′-bipy = 2,2′-bipyridine) has been hydrothermally synthesized. Each of the 1D chains was linked via π–π stacking interactions and formed a supramolecular framework. Furthermore, due to the existence of uncoordinated –COOH groups, the terbium-functionalized hybrid (Tb3+@Zn-CP) was prepared by introducing Tb3+ ions into the structure through coordinated postsynthetic modification (PSM). Tb3+@Zn-CP shows the characteristic emission of Tb3+ ions due to the "antenna effect" of the H3pbc ligand. Based on the excellent luminescence properties and structural stabilities of Zn-CP and Tb3+@Zn-CP, they can be used as highly sensitive and selective luminescent probes of the UV filter BP (benzophenone) depending on multiquenching effects. In addition, their obvious color change can be easily distinguished by the naked eye under ultraviolet light, which was successfully used in the preparation of portable BP test paper. More importantly, Tb3+@Zn-CP is the first example of CPs as a ratiometric luminescent sensor for BP. This work provides a novel strategy for the construction of ratiometric luminescent probes of BP-type UVFs through coordinated postsynthetic modification. [ABSTRACT FROM AUTHOR]

The development of a highly selective and sensitive optical method for quantitative enantioselective sensing of chiral amino acids in the presence of other amino acid interferences has remained a major challenge to date. Herein, a homochiral metal–organic framework (MOF), [Zn(L)(2,2′‐bipy)]·H2O (LNNU‐1) (H2L = HOOCC6H4CH2PO(OH)(OC2H5), 2,2′‐bipy = 2,2′‐bipyridine), is designed to interact with tryptophan via multiple noncovalent interactions. The interactions result in the emergence of a strong induced circular dichroism signal. This enables accurate determination of the absolute configuration and enantiomeric ratio of chiral tryptophan in water, mixed natural amino acids, and blood plasma components without any interference from other coexistent species. A simple device with advantageous characteristics of reusability and simple manipulation is designed for enantioselective sensing assay. The obtained results suggest that the rationally designed homochiral MOF is a promising candidate for enantioselective sensing of chiral species. [ABSTRACT FROM AUTHOR]

With the use of the tailored cyanometalate precursor, Bu4N[Fe(Tp*)(CN)3] (Tp* = hydridotris(3,5-dimethylpyrazol-1yl)borate), as the building block to react with fully solvated MII cations, three new one-dimensional (1D) heterobimetallic cyano-bridged chain complexes of squares, {[Fe(Tp*)(CN)3]2M (CH3CH2OH)2}·4H2O (M = Mn(1), Fe(2), Co(3)), have been prepared. In these compounds, the MII ions have slightly distorted octahedral coordination geometries, and they were bridged by [Fe(Tp*)(CN)3]− to form similar 1D chains of squares. The magnetic studies demonstrated that compound 1 exhibited weak ferromagnetism due to spin canting, compound 2 showed ferrimagnetic behavior in a low temperature region, whereas compound 3 indicated the presence of typical antiferromagnetic coupling. [ABSTRACT FROM AUTHOR]

A cyanide-bridged Fe Co double zigzag chain, {[Fe(bipy)(CN)]Co(btab)} [bipy=2,2′-bipyridine, btab=4,4′-(1,3-phenylene)-bis-4 H-1,2,4-triazole] ( 1), was obtained with tetracyanometalate precursors and Co ions. The chains were further linked by the ditopic btab ligands to a layer. Magnetic property studies demonstrate that 1 shows both metamagnetism with a critical field H =400 Oe and single-chain magnet behavior. [ABSTRACT FROM AUTHOR]