Chiral Luminescent Sensor Eu-BTB@d-Carnitine Applied in the Highly Effective Ratiometric Sensing of Curing Drugs and Biomarkers for Diabetes and Hypertension.

Chiral drugs are of great significance in drug development and life science because one pair of enantiomers has a different combination mode with target biological active sites, leading to a vast difference in physical activity. Metal-organic framework (MOF)-based chiral hybrid materials with specific chiral sites have excellent applications in the highly effective sensing of drug enantiomers. Sitagliptin and clonidine are effective curing drugs for controlling diabetes and hypertension, while insulin and norepinephrine are the biomarkers of these two diseases. Excessive use of sitagliptin and clonidine can cause side effects such as stomach pain, nausea, and headaches. Herein, through post-synthetic strategy, MOF-based chiral hybrid material Eu-BTB@d-carnitine (H3BTB = 1,3,5-benzenetrisbenzoic acid) was synthesized. Eu-BTB@d-carnitine has dual emission peaks at 417 and 616 nm when excited at 330 nm. Eu-BTB@d-carnitine can be applied in luminescent recognition toward sitagliptin and clonidine with high sensitivity and low detection limit (for sitagliptin detection, Ksv is 7.43 × 106 [M-1]; for clonidine detection, Ksv is 9.09 × 106 [M-1]; limit of detection (LOD) for sitagliptin is 10.21 nM, and LOD of clonidine is 8.34 nM). In addition, Eu-BTB@d-carnitine can further realize highly sensitive detection of insulin in human fluids with a high Ksv (2.08 × 106 [M-1]) and a low LOD (15.48 nM). On the other hand, norepinephrine also can be successfully discriminated by the hybrid luminescent platform of Eu-BTB@d-carnitine and clonidine with a high Ksv value of 4.79 × 106 [M-1] and a low LOD of 8.37 nM. As a result, the chiral hybrid material Eu-BTB@d-carnitine can be successfully applied in the highly effective ratiometric sensing of curing drugs and biomarkers for diabetes and hypertension.

Convenient ultrasonic preparation of a water stable cluster-based Cadmium(II) coordination material and highly sensitive fluorescent sensing for biomarkers DPA and 5-HT.

In recent years, a new type of micro-porous material, namely metal organic framework material, has received more and more attention from many basic and industrial fields because these materials possess unique advantages. In this work, through the powerful sonochemical preparation method, a three-dimensional cluster-based CdII-MOFs, {[Cd(abtz)2(H2O)2]·(ClO4)2·H2O}n (1, abtz = 1-(4-aminobenzyl)-1H-1,2,4-triazole) can be quickly synthesized in the facile ultrasonic method. Powder X-ray diffraction (PXRD) measurement confirms that these bulky samples 1 (synthesized on different ultrasonic powers and ultrasonic time conditions) were pure. In addition, ultrasonic chemical time and irradiation power did not change the structure of composites materials 1. SEM and morphological changes of 1 in the ultrasonic synthesis are also determined. Moreover, 1 exhibits good stability, the structure of 1 can be maintained not just in various solvents, and in aqueous environments with pH values from 2 to 12. Photo-luminescent experiment also reveals that complex 1 has the excellent application prospect as highly sensitive sensing material for the biomarker DPA (2,6-pyridine dicarboxylic acid) and 5-HT (5-hydroxytryptamine) through the photo-luminescence "turn-on" and "turn-off" effect, respectively. Further photo-luminescent measurements also show that different ultrasonic powers and ultrasonic time can effectively induce fluorescent sensing enhancement for biomarkers DPA and 5-HT based on the water stable clustered-based cadmium(II) coordination framework.

Hydrothermal synthesis of two-dimensional cadmium(II) micro-porous coordination material based on Bi-functional building block and its application in highly sensitive detection of Fe3+ and Cr2O72.

Metal-organic framework (MOFs), also known as porous coordination polymers (PCPs), is a new kind of crystalline porous materials, which has received extensive attention in the past few decades. As a new type of sensing material, MOFs stand out from many other traditional fluorescence sensors because of its crystal characteristics, structural diversity, stable porosity and adjustable functional characteristics. In this work, the bi-functional building block containing aromatic carboxylic acid and triazole moieties, namely 3-(1H-1,3,4-triazol-1-yl) benzoic acid, was selected as the linker to synthesize {[Cd(µ5-L)⋅I}n (1, HL = 3-(1H-1,3,4-triazol-1-yl)benzoic acid) by hydrothermal method with transition CdII metal centers. Firstly, the preliminary characterization of 1 was carried out by means of PXRD, FT-IR, and then the UV and fluorescence tests were conducted to study the fluorescence properties of 1. The crystal structure analysis indicates that CdII is the center and the ligand is bridged to form a two-dimensional porous structure. In addition, 1 has good selectivity for Fe3+ and Cr2O72-, meanwhile, it has high detection sensitivity (Ksv quenching efficiency for Fe3+: 1.2 × 104 M-1 and Cr2O72- 1.85 × 104 M-1) and low detection limit (Fe3+: 19.21 µM and Cr2O72-: 12.46 µM). The results of photoluminescence test show that 1 can detect cations and anions with high sensitivity, resist the interference of other ions, and have good reusability. As far as we know, 1 is the first example of ultra-stable two-dimensional (2D) Cadmium (II) microporous coordination material as a fluorescence sensor for Fe3+ and Cr2O72-.

Solvothermal preparation of luminescent zinc(II) and cadmium(II) coordination complexes based on the new bi-functional building block and photo-luminescent sensing for Cu2+, Al3+ and L-lysine.

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)2·4H2O] (complex 1) and [Cd(L)2·4H2O] (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+(Ksv = 1.5570 × 104 [M]-1), Cu2+(Ksv = 1.4948 × 104 [M]-1) and L-lysine (Ksv = 4.9118 × 104 [M]-1) with low detection limits (17.5 µM, 18.2 µM, 5.6 µM) respectively.