Anchored atomic tungsten on a B40 cage: a highly active and selective single-atom catalyst for nitrogen reduction.

In comparison with the prevalent 2D material-supported single atom catalysts (SACs), the design and fabrication of SACs with single molecule substrates are still challenging. Here we introduce a new type of SAC in which a recently identified all-boron fullerene B40 is employed as the support and its catalytic performance toward the nitrogen reduction reaction (NRR) process is explored in theory. Taking advantage of the novel heptagonal ring substructure on the sphere and the electron-deficient nature of boron, the atomic metals are facile to reside on B40 to form atomically dispersed η7-B40M exohedral complexes. Among a series of candidates, originating from the proper metal-adsorbate interactions, the atomic tungsten-decorated B40W is screened out as the most feasible catalyst for the NRR with a low over-potential and high selectivity to passivate the competitive hydrogen evolution process.

Novel nucleic acid detection strategies based on CRISPR-Cas systems: From construction to application.

Beyond their widespread application as genome-editing and regulatory tools, clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated (Cas) systems also play a critical role in nucleic acid detection due to their high sensitivity and specificity. Recently developed Cas family effectors have opened the door to the development of new strategies for detecting different types of nucleic acids for a variety of purposes. Precise and efficient nucleic acid detection using CRISPR-Cas systems has the potential to advance both basic and applied biological research. In this review, we summarize the CRISPR-Cas systems used for the recognition and detection of specific nucleic acids for different purposes, including the detection of genomic DNA, nongenomic DNA, RNA, and pathogenic microbe genomes. Current challenges and further applications of CRISPR-based detection methods will be discussed according to the most recent developments.

Functionalized Silicas for Metal-Free and Metal-Based Catalytic Applications: A Review in Perspective of Green Chemistry.

Heterogeneous catalysis plays a key role in promoting green chemistry through many routes. The functionalizable reactive silanols highlight silica as a beguiling support for the preparation of heterogeneous catalysts. Metal active sites anchored on functionalized silica (FS) usually demonstrate the better dispersion and stability due to their firm chemical interaction with FSs. Having certain functional groups in structure, FSs can act as the useful catalysts for few organic reactions even without the need of metal active sites which are termed as the covetous reusable organocatalysts. Magnetic FSs have laid the platform where the effortless recovery of catalysts is realized just using an external magnet, resulting in the simplified reaction procedure. Using FSs of multiple functional groups, we can envisage the shortened reaction pathway and, reduced chemical uses and chemical wastes. Unstable bio-molecules like enzymes have been stabilized when they get chemically anchored on FSs. The resultant solid bio-catalysts exhibited very good reusability in many catalytic reactions. Getting provoked from the green chemistry aspects and benefits of FS-based catalysts, we confer the recent literature and progress focusing on the significance of FSs in heterogeneous catalysis. This review covers the preparative methods, types and catalytic applications of FSs. A special emphasis is given to the metal-free FS catalysts, multiple FS-based catalysts and magnetic FSs. Through this review, we presume that the contribution of FSs to green chemistry can be well understood. The future perspective of FSs and the improvements still required for implementing FS-based catalysts in practical applications have been narrated at the end of this review.

Quorum-sensing based small RNA regulation for dynamic and tuneable gene expression.

OBJECTIVES: Developing a dynamic regulation strategy is an essential step in establishing an automatic control system for manipulating metabolic fluxes and cellular behaviors. To broaden the extent of the application, a system that can generally control any gene of interest is demanded. RESULTS: Through characterization and optimization, the strategy repressed the immediate expression incrementally from 0 to 90% during culturing. Moreover, by changing single base pair in the lux box of the Plux promoter, the degree of repression of the target genomic gene was tuned to a difference of 70%. This strategy is expected to control metabolic flux without disrupting cell growth. CONCLUSIONS: We engineered bacterial small RNA to develop a pathway-independent strategy that can dynamically repress the expression of any gene at the posttranscription level.

Molecular Dynamics Simulation Reveals Unique Interplays Between a Tarantula Toxin and Lipid Membranes.

Tarantula toxins compose an important class of spider toxins that target ion channels, and some are known to interact with lipid membranes. In this study, we focus on a tarantula toxin, Jingzhaotoxin-III (JZTx-III) that specifically targets the cardiac voltage-gated sodium channel Na[Formula: see text]1.5 and is suspected to be able to interact with lipid membranes. Here, we use an all-atom model and long-term molecular dynamics simulations to investigate the interactions between JZTx-III and lipid membranes of different compositions. Trajectory analyses show that JZTx-III has no substantial interaction with the neutral 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) lipids, but binds to membranes containing negatively charged 1-palmitoyl-2-oleoyl-sn-glycero-3-[phospho-rac-(1-glycerol)] (POPG). The most intriguing observations in our simulation are the different interactions between the toxin and the membrane in the mixed and pure POPG membrane systems. The POPC/POPG mixed membrane undergoes a phase transition to a rippled phase upon binding of the toxin, while the pure POPG membrane has no apparent change. Moreover, the binding of JZTx-III to both of the mixture and the pure POPG membrane systems induce small conformational changes. The sequence alignment shows that JZTx-III may not partition into the lipid bilayer due to the mutations of a C-terminal hydrophobic residue and some charged residues that affect toxin orientation. Taken together, JZTx-III and lipid membranes have unique effects on each other that may facilitate the specific binding of JZTx-III to Na[Formula: see text]1.5. This computational study also enriches our understanding of the potential complex interactions between spider toxins and lipid membranes.

[A Quick Quantitative Analysis for Group Composition of Coal Liquefaction Oil by Ultraviolet Spectroscopy].

Gas chromatography is now the primary analysis method for the coal liquefaction oil. However, a simple and rapid quantification/qualification of the coal liquefaction oil can hardly be realized, because the coal liquefaction oil is in a heterogeneous state with a long boiling range. The aim of this study was to establish a rapid and accurate method for the quantification of phenolic compounds, aromatics and aliphatic hydrocarbons in coal liquefaction oil. A representative composition of coal liquefaction light oil, i.e., the distillate fractions of the boiling point range 180-200 degrees C, was chosen as the investigated object. The characteristic absorption peaks of the samples in the UV spectra (200-400 nm) were examined, using three kinds of solvents, cyclohexane, ethanol, 50 Wt% NaOH/ethanol mixture. Among them, the mixture solvent provided the best performance, where the aromatics interfered minimally with the quantification of phenolic compounds by avoiding the peak overlapping problem. By comparison of the UV absorption standard curves between the standard compounds (phenol, m-cresol, p-cresol and o-cresol) and the phenolic mixtures in coal liquefaction oil, m-cresol was selected for the quantification of phenolic compounds in coal liquefaction oil. The content of phenolic compounds was determined to be 32.14% according to the calibration curve of m-cresol at 290 nm, and this result is largely consistent with that determined by weighing after separation. Based on UV and GC analysis of the dephenolized oil, the standard curve of tetrahydronaphthalene at 266 nm was used for the quantification of aromatic hydrocarbons in coal liquefaction oil. The contents of aromatic and aliphatic hydrocarbons were determined to be 44.91% and 22.95%, respectively. To verify the accuracy of the method, recovery of added standards in the oil samples was determined and found to be 104.3%-110.75% and 84.3%-91.75% for phenolic compounds and aromatics, respectively. These results indicate that the contents of phenolic compounds and aromatics can be determined simultaneously with the UV standard curves of m-cresol and tetrahydronaphthalene, respectively, and the aliphatic compounds can be determined by difference.

Effect of mode of delivery on perceived risks of maternal health outcomes among expectant parents: a cohort study in Beijing, China.

BACKGROUND: Misperceptions regarding maternal health outcomes after vaginal delivery (VD) and cesarean delivery (CD) may contribute to the increasing trend towards CD. The effects of mode of delivery on parents' perceived risks of health outcomes are unclear. This study aimed to compare the perceived risks of maternal health outcomes among pregnant women and their partners before and after delivery, and to evaluate factors related to inaccurate perceptions among women after delivery. METHODS: Consecutive eligible nulliparous women at 36-40 weeks gestation were approached during antenatal registration for electronic fetal monitoring, regardless of whether CD or VD was planned. Eligible women were aged 18-45 years, received antenatal care and planned delivery at the First Hospital of Tsinghua University, Beijing, and had partners who could be approached. Concerns about 12 maternal health outcomes were identified by literature search and validated using the content validity index. Women and their partners were questioned anonymously about the perceived risks of outcomes after CD and VD before delivery, and the perceived risks of the delivery experienced at 2-3 days after delivery. Perceived risks were compared with reported risks, and factors associated with inaccurate perceptions were evaluated. RESULTS: Among 272 couples approached, 264 women (97%) and 257 partners (94%) completed the questionnaire both before and after delivery. After CD, the perceived risk of seven health outcomes decreased in women and the perceived risk of two health outcomes increased in partners. After VD, the perceived risk of two outcomes decreased and of one outcome increased in women, and the perceived risk of three outcomes increased in partners. Women perceived higher risks of long-term perineal pain, pelvic organ prolapse, urinary/fecal incontinence, sexual dissatisfaction, and negative impact on the couple's relationship after VD than after CD (all p < 0.05). CD was the most common factor associated with inaccurate perceptions among women after delivery. CONCLUSIONS: The perceived risks of maternal health outcomes decreased after delivery in women and increased after delivery in their partners. Women continued to have inaccurate perceptions of the risks of health outcomes after delivery, indicating that further education is important.

Change of childbirth preference after delivery among nulliparous Chinese women and their partners.

AIM: The aim of the present study was to assess the effect of childbirth preference among nulliparous Chinese women and their partners on actual mode of delivery, and to assess women's change in preference from vaginal delivery to cesarean and the factors associated with this change. METHODS: A cohort study was conducted from July to October 2011 in the First Hospital of Tsinghua University, Beijing. Nulliparous women at the gestational age of 36-40 weeks and their partners were included. Their childbirth preference was recorded twice: once in pregnancy and again 2 or 3 days post-partum. RESULTS: Women preferring cesarean during pregnancy had a 3.9-fold higher chance of undergoing a cesarean than those preferring vaginal delivery (P = 0.004), while the partner's preference had no effect (P = 0.35). Preference for cesarean in the post-partum period increased significantly compared to that during pregnancy both among women, whose preference increased from 10.1% to 28.0%, and among their partners, whose preference increased from 7.8% to 16.7% (P < 0.001 for both). The rate of change in women's preference from vaginal delivery to cesarean was 26.0%. Women having high couple's monthly income, who were feeling depressed, whose partner preferred cesarean during pregnancy or who delivered by cesarean were more likely to experience this change due to fear of labor pain and perineal cutting and a greater perceived safety of cesarean. CONCLUSION: Women's cesarean preference during pregnancy was associated with actual cesarean delivery. Inadequate quality of care in labor and delivery and overestimation of cesarean safety underlie post-partum women's increased preference for cesarean.

Detection of microvesicle miRNA expression in ALL subtypes and analysis of their functional roles.

Microvesicles (MVs) are the heterogeneous mixtures of vesicles. MVs released by leukemia cells constitute an important part of the leukemia microenvironment. MVs might act as important reservoirs of microRNAs (miRNAs). It is worth evaluating whether MVs possess some unique miRNA contents that are valuable in understanding the pathogenesis. In this study, we investigated the miRNA expression patterns of Nalm-6-derived MVs, Jurkat-derived MVs and normal cell-derived MVs using miRNA microarrays. The potential target genes regulated by differentially expressed miRNAs were also predicted and analyzed. Results demonstrated that 182 miRNAs and 166 miRNAs were differentially expressed in Nalm-6-MVs and Jurkat-MVs, respectively. Many oncogenes, tumor suppressors and signal pathway genes were targeted by these aberrantly expressed miRNAs, which might contribute to the development of B-ALL or T-ALL. Our findings expanded the potential diagnostic markers of ALL and provided useful information for ALL pathogenesis.

Impact of open hepatectomy on postoperative bile leakage in patients with biliary tract cancer.

BACKGROUND: Bile leakage is a common and serious complication of open hepatectomy for the treatment of biliary tract cancer. AIM: To evaluate the incidence, risk factors, and management of bile leakage after open hepatectomy in patients with biliary tract cancer. METHODS: We retrospectively analyzed 120 patients who underwent open hepatectomy for biliary tract cancer from February 2018 to February 2023. Bile leak was defined as bile drainage from the surgical site or drain or the presence of a biloma on imaging. The incidence, severity, timing, location, and treatment of the bile leaks were recorded. The risk factors for bile leakage were analyzed using univariate and multivariate logistic regression analyses. RESULTS: The incidence of bile leak was 16.7% (20/120), and most cases were grade A (75%, 15/20) according to the International Study Group of Liver Surgery classification. The median time of onset was 5 d (range, 1-14 d), and the median duration was 7 d (range, 2-28 d). The most common location of bile leakage was the cut surface of the liver (70%, 14/20), followed by the anastomosis site (25%, 5/20) and the cystic duct stump (5%, 1/20). Most bile leaks were treated conservatively with drainage, antibiotics, and nutritional support (85%, 17/20), whereas some required endoscopic retrograde cholangiopancreatography with stenting (10%, 2/20) or percutaneous transhepatic cholangiography with drainage (5%, 1/20). Risk factors for bile leakage include male sex, hepatocellular carcinoma, major hepatectomy, blood loss, and blood transfusion. CONCLUSION: Bile leakage is a frequent complication of open hepatectomy for biliary tract cancer. However, most cases are mild and can be conservatively managed. Male sex, hepatocellular carcinoma, major hepatectomy, blood loss, and blood transfusion were associated with an increased risk of bile leak.

[Macromolecular aromatic network characteristics of Chinese power coal analyzed by synchronous fluorescence and X-ray diffraction].

Coal structure, especially the macromolecular aromatic skeleton structure, has a strong influence on coke reactivity and coal gasification, so it is the key to grasp the macromolecular aromatic skeleton coal structure for getting the reasonable high efficiency utilization of coal. However, it is difficult to acquire their information due to the complex compositions and structure of coal. It has been found that the macromolecular aromatic network coal structure would be most isolated if small molecular of coal was first extracted. Then the macromolecular aromatic skeleton coal structure would be clearly analyzed by instruments, such as X-ray diffraction (XRD), fluorescence spectroscopy with synchronous mode (Syn-F), Gel permeation chromatography (GPC) etc. Based on the previous results, according to the stepwise fractional liquid extraction, two Chinese typical power coals, PS and HDG, were extracted by silica gel as stationary phase and acetonitrile, tetrahydrofuran (THF), pyridine and 1-methyl-2-pyrollidinone (NMP) as a solvent group for sequential elution. GPC, Syn-F and XRD were applied to investigate molecular mass distribution, condensed aromatic structure and crystal characteristics. The results showed that the size of aromatic layers (La) is small (3-3.95 nm) and the stacking heights (Lc) are 0.8-1.2 nm. The molecular mass distribution of the macromolecular aromatic network structure is between 400 and 1 130 amu, with condensed aromatic numbers of 3-7 in the structure units.

Overcoming Limitations in the Strong Interaction between Pt and Irreducible SiO2 Enables Efficient and Selective Hydrogenation of Anthracene.

Interactions between metals and oxide supports are crucial in determining catalytic activity, selectivity, and stability. For reducible oxide supported noble metals, a strong metal-support interaction (SMSI) has been widely recognized. Herein we report the intermediate selectivity and stability over an irreducible SiO2 supported Pt catalyst in the hydrogenation of anthracene that are significantly boosted due to the SMSI-induced formation of intermetallic Pt silicide and Pt-SiO2 interface. The limitation in the strong interaction between Pt nanoparticles and irreducible SiO2 has been breached by combining the strong electrostatic adsorption method and following the high temperature reduction strategy. Due to the isolated Pt active sites by Si atoms, the activated H species produced over the Pt2Si/SiO2 catalyst with an initial catalytic activity of 2.49 µmol/(m2/g)/h as well as TOF of 0.95 s-1 preferentially transfer to the outer ring of anthracene to 87% yield of symmetric octahydroanthracene (sym-OHA) by subsequent hydrogenation. In addition, the Pt2Si/SiO2 catalyst presents an excellent stability after five cycles, which can be attributed to the fact that intermetallic Pt2Si nanoparticles are anchored firmly onto the surface of the SiO2 support. The discovery contributes to broaden the horizons on the SMSI effect in the irreducible oxide supported metal particle catalysts and provides guidance to design the metal-SiO2 interface and tune the surface chemical properties in diverse application conditions.

SIRT3 deficiency increases mitochondrial oxidative stress and promotes migration of retinal pigment epithelial cells.

Retinal pigment epithelial cells are closely associated with the pathogenesis of diabetic retinopathy. The mechanism by which diabetes impacts retinal pigment epithelial cell function is of significant interest. Sirtuins are an important class of proteins that primarily possess nicotinamide adenine dinucleotide-dependent deacetylases activity and involved in various cellular physiological and pathological processes. Here, we aimed to examine the role of sirtuins in the induction of diabetes-associated retinal pigment epithelial cell dysfunction. High glucose and platelet-derived growth factor (PDGF) treatment induced epithelial-mesenchymal transition and the migration of retinal pigment epithelial cells, and decreased sirtuin-3 expression. Sirtuin-3 knockdown using siRNA increased epithelial-mesenchymal transition and migration of retinal pigment epithelial cells. In contrast, sirtuin-3 overexpression attenuated the effects caused by high glucose and PDGF on epithelial-mesenchymal transition and migration of retinal pigment epithelial cells, suggesting that sirtuin-3 deficiency contributed to retinal pigment epithelial cell dysfunction induced by high glucose and PDGF. Mechanistically, sirtuin-3 deficiency induced retinal pigment epithelial cell dysfunction by the overproduction of mitochondrial reactive oxygen species. These results suggest that sirtuin-3 deficiency mediates the migration of retinal pigment epithelial cells, at least partially by increasing mitochondrial oxidative stress, and shed light on the importance of sirtuin-3 and mitochondrial reactive oxygen species as potential targets in diabetic retinopathy therapy.

Intermetallic PdZn nanoparticles catalyze the continuous-flow hydrogenation of alkynols to cis-enols.

Designing highly active and stable lead-free palladium-based catalysts without introducing surfactants and stabilizers is vital for large-scale and high-efficiency manufacturing of cis-enols via continuous-flow semi-hydrogenation of alkynols. Herein, we report an intermetallic PdZn/ZnO catalyst, designed by using the coupling strategy of strong electrostatic adsorption and reactive metal-support interaction, which can be used as a credible alternative to the commercial PdAg/Al2O3 and Lindlar catalysts. Intermetallic PdZn nanoparticles with electron-poor active sites on a Pd/ZnO catalyst significantly boost the thermodynamic selectivity with respect to the mechanistic selectivity and therefore enhance the selectivity towards cis-enols. Based on in situ diffuse reflectance infrared Fourier-transform spectra as well as simulations, we identify that the preferential adsorption of alkynol over enol on PdZn nanoparticles suppresses the over-hydrogenation of enols. These results suggest the application of fine surface engineering technology in oxide-supported metal (particles) could tune the ensemble and ligand effects of metallic active sites and achieve directional hydrogenation in fine chemical synthesis.

Synthesis of Ni/NiAlOx Catalysts for Hydrogenation Saturation of Phenanthrene.

The saturation of octahydrophenanthrene was the rate-determining step in the hydrogenation process from phenanthrene to perhydrophenanthrene, which was due to the steric hindrance and competitive adsorption of octahydrophenanthrene. In this work, a series of Ni/NiAlOx catalysts with a uniform electron-deficient state of Ni derived from the nickel aluminate structure was synthesized to overcome the disadvantage of noble catalyst and the traditional sulfided catalysts in the saturation hydrogenation process of phenanthrene. Results showed that the catalyst calcinated at 650°C possessed more Ni2+ (∼98%) occupying octahedral sites and exhibited the highest robs (1.53 × 10-3 mol kg-1 s-1) and TOF (14.64 × 10-3 s-1) for phenanthrene hydrogenation. Furthermore, its ability to overcome steric hindrance and promote the rate-determining step was proven by octahydrophenanthrene hydrogenation. Comparing the evolution of hydrogenation activity with the change in the electronic structure of surface Ni sites, it was shown that the increase of metallic electron deficiency hindered the π-back bonding between surface Ni and aromatic rings, which was unfavorable for aromatic adsorption. As a result, the phenanthrene hydrogenation saturation performance can be enhanced by stabilizing the electron-deficient state of surface Ni on an optimal degree.

Desulfurization on Boron Nitride and Boron Nitride-based Materials.

Combustion of liquid fuels containing sulfur compounds is highly unfavorable due to the adverse effects caused by the resultant SOx emission. Consequently, catalytic and adsorptive materials having the capacity to eliminate the sulfur compounds from liquid fuels are very attractive. Hexagonal boron nitride (BN), with its interesting chemical and physical properties, finds applications in diverse fields, especially in energy and environmental applications. Recently, BN and BN-based materials have gained significant interest in emerging desulfurization processes such as oxidative desulfurization and adsorptive desulfurization. In this review, BN and BN-based materials are elaborately discussed in the context of their use in various desulfurization techniques. A brief description about the different desulfurization processes is provided at the outset. The relationship between the characteristics (the defects, morphology, porosity and surface area) of BN and desulfurization efficiency is also summarized. Furthermore, the mechanistic insights regarding the action of BN materials in the desulfurization processes are discussed. With this review, the synthetic strategies for designing the novel BN-based catalysts/adsorbents for the effective desulfurization of liquid fuels can be grasped.

Naphthalene Hydrogenation Saturation over Ni2P/Al2O3 Catalysts Synthesized by Thermal Decomposition of Hypophosphite.

A series of Ni2P/Al2O3 catalysts with different Ni2P loadings were synthesized via thermal decomposition of hypophosphite and employed for naphthalene hydrogenation saturation. Results showed that Ni2P loading greatly affected Ni2P particle size and the number of active sites of the as-synthesized catalysts, which was derived from the variable interaction between POx and Al2O3. When the hydrogenation saturation reaction was performed at 300 °C, 4 MPa, a H2/oil volume ratio of 600, and a liquid hourly space velocity (LHSV) of 3 h-1, 98% naphthalene conversion and 98% selectivity to decalin were achieved over Ni2P/Al2O3 catalysts with 10 wt % Ni2P. The superior naphthalene hydrogenation saturation performance was ascribed to the large specific surface area (169 m2·g-1), small Ni2P particle size (3.8 nm), and the high number of exposed active sites (CO sorption 30 µmol·g-1), which were beneficial to the adsorption and diffusion of the reactant molecules on the catalyst.

Study of fluorescence characteristics of the charge-transfer reaction of quinolone agents with bromanil.

A spectrofluorimetric method was discussed for the determination of three antibacterial quinolone derivatives, ofloxacin (OFL), norfloxacin (NOR) and ciprofloxacin (CIP) through charge-transfer complexation (CTC) with 2,3,5,6-tetrabromo-1,4-benzoquinone (bromanil, TBBQ). The method was based on the reaction of these drugs as n-electron donors with the pi-acceptor TBBQ. TBBQ was found to react with these drugs to produce a kind of yellow complexes and the fluorescence intensities of the complexes were enhanced by 29-36 times more than those of the corresponding monomers. UV-vis, (1)H NMR and XPS techniques were used to study the complexes formed. The various experimental parameters affecting the fluorescence intensity were studied and optimized. Under optimal reaction conditions, the rectilinear calibration graphs were obtained in the concentration range of 0.021-2.42 microg mL(-1), 0.017-2.63 microg mL(-1) and 0.019-2.14 microg mL(-1) for OFL, NOR and CIP, respectively. The methods developed were applied successfully to the determination of the subject drugs in their pharmaceutical dosage forms with good precision and accuracy compared to official and reported methods as revealed by t- and F-tests.

[Study of cefadroxil and cephradine charge transfer process by fluorescence quenching method].

A simple and sensitive fluorescence quenching method was developed for the examination of cefadroxil and cephradine. The method is based on the reaction of fluorescein with cefadroxil or cephradine, resulting in the formation of complexes with weak fluorescence, i.e. quenching the fluorescence intensity of the system. By the use of absorption spectroscopy, infrared spectroscopy and quantum chemistry calculation the reaction process of the cephalosporins and the bonding of reaction mechanism were basically analyzed. Based on this, the fluorescence spectrometry method for the determination of the contents of cefadroxil and cephradine was developed: The maximum excitation and emission wavelength was at 483 nm, and 517 nm and 519 nm respectively. The linear calibration curves were obtained over the cefadroxil and cephradine concentration ranges of 0.3-13.5 mg x L(-1) and 0.1-1.2 mg x L(-1) respectively. The proposed method has been successfully applied to the examination of the subject drugs in its pharmaceutical dosage with good precision and accuracy. The recoveries are 99.63%-99.91% and 99.71%-100.08% respectively.

A Water-Stable Uranyl Organic Framework as a Highly Selective and Sensitive Bifunctional Luminescent Probe for Fe3+ and Tetracycline Hydrochloride.

A new coordination polymer (H2 bpy)0.5 ⋅[(UO2 )1.5 (ipa)2 (H2 O)] (1) (H2 ipa=isophthalic acid, bpy=4,4'-bipyridine) was synthesized by hydrothermal condition. It was characterized by IR spectroscopy, elemental analysis, TG-DTA analysis, and powder X-ray diffraction. Analysis of single-crystal X-ray diffraction results showed that the title compound exhibited a double chain bridged by the different uranyl ions and ipa2- ligands. Through the hydrogen bond interactions and π⋅⋅⋅π stacking interactions, the double chains were assembled into the three-dimensional supramolecular framework. Furthermore, the compound can be used as a promising bifunctional luminescence sensor for detecting and identifying Fe3+ and tetracycline hydrochloride antibiotic molecules with high selectivity and sensitivity in aqueous solutions. Moreover, the luminescent sensing mechanisms for different analytes were proposed. Moreover, the electronic properties of title compound were explored by density functional theory (DFT) calculations. The sensor system has been successfully applied for the detection of Fe3+ and tetracycline hydrochloride with high recovery percentages and low relative standard deviation in real river water samples.