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DL-mandelic acid (MA) has been intercalated into Zn-Al layered double hydroxide (LDH) by an anion-exchange reaction. After intercalation of MA anions, the basal spacing of the LDH increased from 0.75 to 1.46 nm, suggesting that the MA anions were successfully intercalated into the interlayer galleries of the LDH. The structure and the thermal stability of the samples were characterized by XRD, FT-IR, TG-DTA. Studies of MA release from ZnAl-MA-LDH in hydrochloric solution (pH = 4) imply that ZnAl-MA-LDH is a better controlled release system than pure MA. Meanwhile, the mechanisms of slow release were assessed by using four commonly kinetic models. Finally, the antimicrobial activity of ZnAl-MA-LDH was tested against two kinds of bacteria and a fungus. The study confirms that the mandelic ions intercalated LDHs have the potential application as a slow release preservative in the future., (Copyright © 2018 Elsevier B.V. All rights reserved.)

In this work, a novel water-stable coordination polymer with {4 4 } network topology {[Zn(L) 2 (NO 3 ) 2 ]} n ( 1 ) (L = 4,4′-Bis(triazol-1-ylmethyl)biphenyl) has been synthesized through the hydrothermal and sonochemical approaches. 1 has been characterized by single crystal X-ray diffraction, powder X-ray diffraction (PXRD), Fourier Transform Infrared Spectroscopy, UV–vis absorption spectrum and scanning electron microscopy (SEM). PXRD patterns of the as-synthesized samples 1 have confirmed the purity of the bulky samples. In the sonochemical preparation approaches, different ultrasound irradiation power and ultrasound time were also used in order to investigate the impact factor for morphology and size of nano-structured 1 . Photo-luminescence studies have revealed that 1 can efficiently distinguish Fe 3+ from Fe 2+ and other metal ions. On the other hand, 1 also can exhibit a highly sensitive, excellently selective and real-time detection of benzaldehyde and pH through photo-luminescence quenching process. As for 1 , density functional theory (DFT) and time-dependent DFT (TDDFT) theory has been applied to calculate these spectroscopic data, the result agree with the experimental results for detection of benzaldehyde. Photo-luminescent recyclability results indicated 1 can be reused at least five times in the detection process. To the best of our knowledge, this is the first example of a multi-responsive regenerable luminescent sensor for highly selective, sensitive and real-time sensing of Fe 3+ over Fe 2+ , benzaldehyde and pH values. [ABSTRACT FROM AUTHOR]

Two cadmium(II) and two zinc(II) coordination complexes with diverse structural motifs, [Cd2(HL)I3H2O]·H2O (1), [Cd2(H2L)2(H2O)4]·2SO4·14H2O (2), [Zn3(L′)2(H2O)6]·4H2O·2(NO3) (3), and [Zn3L'2(H2O)2Cl2]·H2O (4) [H2L = 1,1‐bis(5‐(pyrid‐2‐yl)‐1,2,4‐triazol‐3‐yl)methane; H2L′ = 1,1‐bis(5‐(pyrid‐2‐yl)‐1,2,4‐triazol‐3‐yl)methanone] were synthesized through a hydrothermal method. These coordination complexes were characterized by single‐crystal X‐ray diffraction, powder X‐ray diffraction (PXRD), FT‐IR spectroscopy, and photo‐luminescent experiments. Single crystal structural analysis revealed that 1–4 belong to polynuclear coordination compounds. PXRD analysis of 1–4 unambiguously confirmed the purity of the as‐synthesized coordination compounds. It is the first time to synthesize coordination compounds based on H2L′, which reacted from the original material H2L through in‐situ hydrothermal conditions. In addition, photo‐luminescent experiments revealed that 1–4 have real‐time sensing effects for benzaldehyde through fluorescence quenching. For 1–4, the photo‐luminescent quenching effect for benzaldehyde was also compared and the coordination complexes 3 and 4 based on H2L′ have higher photo‐luminescent quenching effect than compounds 1 and 2. [ABSTRACT FROM AUTHOR]

• Two new coordination complexes based on 4′-(1H-1,2,4-triazole-1-yl)-[1,1′-biphenyl]-4-carboxylic acid have been synthesized. • Photo-luminescent experiment reveals that 1 can accurately recognize Al3+ and Cu2+with excellent selectivity and sensitivity. • 1 can recognize L-lysine with excellent sensitivity (K sv = 4.9118 × 104 [M]−1). In industry, over usage of Cu2+ and Al3+ will lead to toxic wastewater, which further to give serious pollution for the environment. On the other hand, L-lysine can enhance serotonin release in the amygdala, with subsequent changes in psychobehavioral responses to stress. Therefore it is the urgent problem to design a method for detecting the amount of Cu2+, Al3+, and L-lysine. In this work, through the solvothermal synthesis method, two new coordination complexes based on the new bifunctional building block 4′-(1H-1,2,4-triazole-1-yl)- [1,1′-biphenyl]-4-carboxylic acid (HL) have been synthesized, namely, [Zn(L) 2 ·4H 2 O] (complex 1) and [Cd(L) 2 ·4H 2 O] (complex 2). X-ray single-crystal diffractometer was used to analyze its structure, powder X-ray diffraction (PXRD) patterns confirmed that 1 and 2 powder's purity and 1 can keep stable during the detection process of Cu2+, Al3+, and L-lysine, respectively. Elemental analysis, thermogravimetric analysis, infrared analysis, ultraviolet analysis and fluorescent spectrum have been used to characterize these complexes. The photo-luminescent test showed that 1 can accurately recognize Al3+ and Cu2+ among various cations. On the other hand, 1 can distinguish L-lysine among amino acid molecules. Therefore, 1 can be utilized as a multifunctional fluorescent probe for Al3+(K sv = 1.5570 × 104 [M]−1), Cu2+(K sv = 1.4948 × 104 [M]−1) and L-lysine (K sv = 4.9118 × 104 [M]−1) with low detection limits (17.5 μM, 18.2 μM, 5.6 μM) respectively. [ABSTRACT FROM AUTHOR]