U-shaped association between serum 25-hydroxyvitamin D concentrations and urinary leakage among adult females aged 45 years and over in the United States: a cross-sectional study.

BACKGROUND: The relationship between serum vitamin D status and urinary leakage (UL) among middle-aged females needs to be further studied. The aim of this study was to evaluate the association of serum 25-hydroxyvitamin D [25(OH)D] concentrations with UL among American females ages 45 years and over. METHODS: Seven cycles of the National Health and Nutrition Examination Survey (NHANES) with self-report UL data, were used. A total of 9525 women aged 45 years and older were enrolled in this study. Univariate and multivariate logistic regression models and the smooth curve fitting were utilized to analyze the association between clinical UL and serum 25-hydroxyvitamin D [25(OH)D] concentrations. RESULTS: A non-linear relationship between serum 25(OH)D concentrations and clinical ULwas observed. When serum 25(OH)D concentration was higher than the inflection point 63.5 nmol/L, a positive correlation was observed between serum 25(OH)D concentrations and clinical UL ([OR]: 1.007, 95%CI: 1.005-1.009, P < 0.01). However, when serum 25(OH)D concentration was below the inflection point 63.5 nmol/L, a negative correlation was observed between serum 25(OH)D concentrations and clinical UL ([OR]: 0.993, 95%CI: 0.989-0.996, P < 0.01). CONCLUSIONS: The association between serum vitamin D and the risk of UL exhibited a U-shaped pattern among US middle-aged females, with an inflection point occurring at a serum 25(OH)D concentration of 63.5 nmol/L.

Fast Detection of Entacapone by a Lanthanide-Organic Framework with Rhombic Channels.

Entacapone (ENT) is a powerful catechol-O-methyl transferase inhibitor that is used for the diagnosis and treatment of Parkinson's syndrome, but the amount used must be well controlled to avoid overtreatment and side effect. Fast and selective detection of ENT needs well-matched energy levels and well-designed sensor-ENT interaction which is highly challenging. In this work, a water stable europium-based metal-organic framework (Eu-TDA) was synthesized to detect ENT by luminescence with excellent reusability and selectivity in the presence of main coexisting and interference species of plasma with a limit of detection of 5.01 µM. The experimental results showed that the luminescence of Eu-TDA can be effectively quenched by ENT via well-designed photoinduced electron transfer mechanism and internal filtration effect mechanism in the system.

Respiratory syncytial virus infection-induced mucus secretion by down-regulation of miR-34b/c-5p expression in airway epithelial cells.

Severe RSV infection is the main cause of hospitalization to children under the age of five. The regulation of miRNAs on the severity of RSV infection is unclear. The aim of the study was to identify the critical differential expression miRNAs (DE miRNAs) that can regulate the pathological response in RSV-infected airway epithelial cells. In this study, miRNA and mRNA chips of RSV-infected airway epithelia from Gene Expression Omnibus (GEO) were screened and analysed, separately. DE miRNAs-targeted genes were performed for further pathway and process enrichment analysis. DE miRNA-targeted gene functional network was constructed on the basis of miRNA-mRNA interaction. The screened critical miRNA was also investigated by bioinformatics analysis. Then, RSV-infected human bronchial epithelial cells (HBECs) were constructed to verify the expression of the DE miRNAs. Finally, specific synthetic DE miRNAs mimics were used to confirm the effect of DE miRNAs on the RSV-infected HBECs. 45 DE miRNAs were identified from GEO62306 dataset. Our results showed that hsa-mir-34b-5p and hsa-mir-34c-5p decreased significantly in HBECs after RSV infection. Consistent with the biometric analysis, hsa-mir-34b/c-5p is involved in the regulation of mucin expression gene MUC5AC. In RSV-infected HBECs, the inducement of MUC5AC production by decreased hsa-mir-34b/c-5p was partly mediated through activation of c-Jun. These findings provide new insights into the mechanism of mucus obstruction after RSV infection and represent valuable targets for RSV infection and airway obstruction treatment.

Airway epithelial ITGB4 deficiency in early life mediates pulmonary spontaneous inflammation and enhanced allergic immune response.

Lung immune responses to respiratory pathogens and allergens are initiated in early life which will further influence the later onset of asthma. The airway epithelia form the first mechanical physical barrier to allergic stimuli and environmental pollutants, which is also the key regulator in the initiation and development of lung immune response. However, the epithelial regulation mechanisms of early-life lung immune responses are far from clear. Our previous study found that integrin ß4 (ITGB4) is decreased in the airway epithelium of asthma patients with specific variant site. ITGB4 deficiency in adult mice aggravated the lung Th2 immune responses and enhanced airway hyper-responsiveness (AHR) with a house dust mite (HDM)-induced asthma model. However, the contribution of ITGB4 to the postnatal lung immune response is still obscure. Here, we further demonstrated that ITGB4 deficiency following birth mediates spontaneous lung inflammation with ILC2 activation and increased infiltration of eosinophils and lymphocytes. Moreover, ITGB4 deficiency regulated thymic stromal lymphopoietin (TSLP) production in airway epithelial cells through EGFR pathways. Neutralization of TSLP inhibited the spontaneous inflammation significantly in ITGB4-deficient mice. Furthermore, we also found that ITGB4 deficiency led to exaggerated lung allergic inflammation response to HDM stress. In all, these findings indicate that ITGB4 deficiency in early life causes spontaneous lung inflammation and induces exaggerated lung inflammation response to HDM aeroallergen.

DNA methylation down-regulates integrin ß4 expression in asthmatic airway epithelial cells.

BACKGROUND: Integrin ß4 (ITGB4) is a hemi-desmosome protein which is downregulated in the airway epithelial cells of asthma patients. The proximal promoters and exons of ITGB4 contain CpG islands or multiple CpG sites both in human and mice, which indicated the possible methylation regulation of ITGB4 in airway epithelial cells. OBJECTIVE: We sought to unveil that DNA methylation regulates the decreased ITGB4 during the pathogenesis of asthma. METHODS: Mice were exposed to house dust mite (HDM) extracts to construct an asthma model. 5-Aza-2'-deoxycytidine (5-AZA) or dexamethasone (DEX) were added in the last two weeks. Besides, the primary human bronchial epithelial (HBE) cells were incubated for the detection of ITGB4 expression and methylation status after HDM stress. Furthermore, DNA methylation of ITGB4 in peripheral blood was measured in asthma patients. Logistic regression was employed to evaluate the association between methylation sites and asthma patients' ages in the control of potential confounders. Moreover, the correlations between differentially methylated sites (DMSs) and clinical parameters in asthma patients were assessed. Finally, the ability of candidate DMSs to predict asthma was evaluated by receiver operating characteristic (ROC) analysis and principal component analysis (PCA). RESULTS: We found that in HDM-stressed asthma model, DNA methylation regulated the reduced ITGB4 expression in airway epithelial cells. Moreover, alteration in the specific CpG sites (chr17:73717720 and chr17:73717636) of ITGB4 may regulate ITGB4 expression and further may be associated with the clinically phenotypic of asthma. The specific DMSs of ITGB4 in peripheral blood can distinguish asthma patients from healthy controls (HCs) effectively. CONCLUSIONS AND CLINICAL RELEVANCE: This study confirmed that DNA methylation regulates the decreased expression of ITGB4 in the airway epithelial cells of asthma patients. These results supply some useful insights to the mechanism of the decreased ITGB4 in asthmatic airway epithelial and provide possible targets for early prediction and screening of asthma.

A Water-Stable Lanthanide Coordination Polymer as Multicenter Platform for Ratiometric Luminescent Sensing Antibiotics.

As a hot topic of global concern, the distinguishing and detecting of antibiotic pollution is crucial owing to its adverse effect on ecosystems and human health stemming from excessive use and poor management. Herein, a water-stable lanthanide coordination polymer sensor (Dy-TCPB) with multiple emitting centers is prepared. The versatile Dy-TCPB can conveniently differentiate various antibiotics, and displays a self-calibration luminescent response to nitrofurazone (NFZ) and furazolidone (FZD). Each antibiotic exhibits notable correlation to a unique combination of the two ligand-to-Dy ion emission intensity ratios, enabling two-dimensional fingerprint recognition. Furthermore, the novel self-calibration sensor demonstrates effective recognition of NFZ and FZD with excellent sensitivity and selectivity, and detection limits as low as 0.0476 and 0.0482 µm for NFZ and FZD, respectively. The synthetic approach for the fabrication of a singular coordination polymer exhibiting multiple emissions provides a promising strategy for the development of facile and effective ratiometric sensors.

Airway epithelial integrin ß4 suppresses allergic inflammation by decreasing CCL17 production.

Airway epithelial cells (AECs) play a key role in asthma susceptibility and severity. Integrin ß4 (ITGB4) is a structural adhesion molecule that is down-regulated in the airway epithelium of asthma patients. Although a few studies hint toward the role of ITGB4 in asthmatic inflammation pathogenesis, their specific resultant effects remain unexplored. In the present study, we determined the role of ITGB4 of AECs in the regulation of Th2 response and identified the underpinning molecular mechanisms. We found that ITGB4 deficiency led to exaggerated lung inflammation and AHR with higher production of CCL17 in house dust mite (HDM)-treated mice. ITGB4 regulated CCL17 production in AECs through EGFR, ERK and NF-κB pathways. EFGR-antagonist treatment or the neutralization of CCL17 both inhibited exaggerated pathological marks in HDM-challenged ITGB4-deficient mice. Together, these results demonstrated the involvement of ITGB4 deficiency in the development of Th2 responses of allergic asthma by down-regulation of EGFR and CCL17 pathway in AECs.

Variable DNA methylation of aging-related genes is associated with male COPD.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a chronic lung inflammatory disease which has a close relationship with aging. Genome-wide analysis reveals that DNA methylation markers vary obviously with age. DNA methylation variations in peripheral blood have the potential to be biomarkers for COPD. However, the specific DNA methylation of aging-related genes in the peripheral blood of COPD patients remains largely unknown. METHODS: Firstly, 9 aging-related differentially expressed genes (DEGs) in COPD patients were screened out from the 25 aging-related genes profile through a comprehensive screening strategy. Secondly, qPCR and multiple targeted bisulfite enrichment sequencing (MethTarget) were used to detect the mRNA level and DNA methylation level of the 9 differentially expressed genes in the peripheral blood of 60 control subjects and 45 COPD patients. The candidate functional CpG sites were selected on the basis of the regulation ability of the target gene expression. Thirdly, the correlation was evaluated between the DNA methylation level of the key CpG sites and the clinical parameters of COPD patients, including forced expiratory volume in one second (FEV1), forced expiratory volume in one second as percentage of predicted volume (FEV1%), forced expiratory volume/ forced vital capacity (FEV/FVC), modified British medical research council (mMRC) score, acute exacerbation frequency and the situation of frequent of acute aggravation (CAT) score. Lastly, differentially methylated CpG sites unrelated to smoking were also determined in COPD patients. RESULTS: Of the 9 differentially expressed aging-related genes, the mRNA expression of 8 genes were detected to be significantly down-regulated in COPD group, compared with control group. Meanwhile, the methylated level of all aging-related genes was changed in COPD group containing 219 COPD-related CpG sites in total. Notably, 27 CpG sites of FOXO3 gene showed a lower False Discovery Rate (FDR) and higher methylation difference values. Also, some variable DNA methylation is associated with the severity of COPD. Additionally, of the 219 COPD-related CpG sites, 147 CpG sites were not related to smoking. CONCLUSION: These results identified that the mRNA expression and DNA methylation level of aging-related genes were changed in male COPD patients, which provides a molecular link between aging and COPD. The identified CpG markers are associated with the severity of COPD and provide new insights into the prediction and identification of COPD.

Efficacy of probiotic supplementary therapy for asthma, allergic rhinitis, and wheeze: a meta-analysis of randomized controlled trials.

Background: Probiotic supplementary therapy to prevent allergic diseases, including asthma in children, has been widely explored in many randomized controlled trials. However, there is conflicting evidence on the effect of probiotic supplementation during pregnancy and infancy to the incidence of asthma and allergic rhinitis. Method: This study was designed to systematically explore the potential effects of probiotic supplementation on the occurrence and development of asthma, wheeze, and allergic rhinitis. Randomized controlled trials were searched in several medical literature data bases. A meta-analysis was undertaken by using the fixed-effects model or the random effects model to calculate the pooled risk of significant heterogeneity. Two writers were designated to perform the study selection and data extraction. The primary outcome was clinically diagnosed asthma; the secondary outcomes included wheeze, allergic rhinitis, and a positive aeroallergen skin-prick test result. Results: Seventeen randomized controlled trials, which composed a total of 5264 children, were analyzed. The pooled data for risk of developing asthma after probiotic supplementation showed no significant reduction compared with controls (risk ratio [RR] 0.86 [95% confidence interval {CI}, 0.73-1.01]; I² = 0%; p = 0.06). A subgroup of strains indicated that Lactobacillus rhamnosus GG supplementation only had a reduction to the occurrence of asthma (RR 0.75 [95% CI, 0.57-0.99]; I² = 11%; p = 0.04). The supplement in the postnatal group had a similar result, but the incorporated data were limited. Meanwhile, it is failed to identify that probiotic supplementary therapy have a clear benefit to the secondary outcomes: wheeze, allergic rhinitis, positive aeroallergen skin-prick test result. Conclusion: This study showed a significant benefit that supplementation with probiotics in pre- and postnatal periods was likely to play an essential strategic role in the prevention of asthma. However, these effects were based on the type of probiotics used, which also need more large-sample and high-quality RCTs to confirm the reliability of this study.

ITGB4 deficiency in bronchial epithelial cells directs airway inflammation and bipolar disorder-related behavior.

BACKGROUND: Chronic persistent airway inflammation has been associated with the comorbidity of asthma and bipolar disorder (BD). However, the direct relevance between airway inflammation and BD-like psychiatric comorbidity is almost unknown. Integrin ß4 (ITGB4) is downregulated on the airway epithelial of asthma patients, which might play a critical role in the parthenogenesis of airway inflammation. So this study aimed to examine the role of ITGB4 deficiency in mediating airway inflammation and further leading to the BD-like behaviors. METHODS: ITGB4-/- mice were generated by mating ITGB4fl/fl mice with CCSP-rtTAtg/-/TetO-Cretg/tg mice. Mania-like behavior tests were performed, including hyperlocomotion, D-amphetamine-induced hyperactivity, open-field test, and elevated plus-maze test. Depressive-like behavior tests were carried out, including sucrose preference, forced swimming, and learned helplessness. Inflammatory cells (Th17, Th1, Th2) in the lung were examined by flow cytometry. Futhermore, inflammatory cytokines (IL-4, IL-13) in bronchoalveolar lavage fluid and sera were detected by ELISA. Protein expression of the IL-4Rα on choroid plexus, microglial marker (IBA1), and synapse-associated proteins (synaptophysin, SYP) in the hippocampus and prefrontal cortex were examined by western blotting. Additionally, proinflammatory cytokines (IL-1ß, IL-6, and TNF-α) in the hippocampus and prefrontal cortex were detected by immunohistochemistry. Inflammatory disorder in the lung, hippocampus, and prefrontal cortex was tested by hematoxylin and eosin (H&E) staining. And cell apoptosis in the hippocampus and prefrontal cortex was measured by TUNEL test. RESULTS: ITGB4-/- mice exhibited mania-like behavior, including hyperlocomotion, D-amphetamine-induced hyperactivity, and reduced anxiety-like behavior. While under stressful conditions, ITGB4-/- mice manifested depressive-like behavior, including anhedonia, behavioral despair, and enhanced learned helplessness. At the same time, ITGB4-/- mice mainly exerted Th2-type inflammation in periphery, like the number and major cytokines IL-4 and IL-13 of Th2-type inflammation. ITGB4-/- mice also showed a significant increase of microglia and pro-inflammatory cytokines such as IL-1ß, IL-6, and TNF-α in the hippocampus and prefrontal cortex. Additionally, neuron damage, increased neuron apoptosis, and the decrease of SYP were found in ITGB4-/- mice. CONCLUSIONS: These findings confirmed that airway inflammatory induced by ITGB4 deficiency is the important incentive for the BD-like behavior during asthma pathogenesis. The ITGB4-deficient mice provide a validated animal model for us to study the possible mechanism of BD-like psychiatric comorbidity of asthma patients.

Three new species of Calocybe (Agaricales, Basidiomycota) from northeastern China are supported by morphological and molecular data.

Three new species, Calocybe aurantiaca, C. convexa, and C. decolorata, are described based on collections made in Shenyang City, Liaoning Province, China. The main characters of C. aurantiaca are its orange-yellow sporocarps and small and smooth basidiospores. Calocybe convexa is characterized by its orange-buff pileus, very small basidiospores, and tortuous stipe, whereas C. decolorata is mainly characterized by its gills that turn blue when bruised. The sequences of nuc rDNA ITS1-5.8S-ITS2 (ITS) and the 28S D1-D5 region of the Calocybe species were analyzed, and the results indicated that the three new species belonged to the genus Calocybe and differed from other species of Calocybe. The morphological similarities of the new species to other Calocybe species and the classification system within the genus Calocybe based on molecular data are also discussed. A key is provided for the Calocybe species as reported from China in order to facilitate future studies of the genus.

Inhibiting miRNA-146a suppresses mouse gallstone formation by regulating LXR/megalin/cubilin-media cholesterol absorption.

Background: miRNA has been implicated in regulating cholesterol homeostasis, a critical factor in gallstone formation. Here, we focused on elucidating the role of miR-146a in this pathological process. Methods: C57BL/6 mice were fed with lithogenic diet (LD) and injected with miR-146 antagomir (anta-146) via the tail vein for various weeks. The gallbladders and liver tissues were collected for cholesterol crystal imaging, gallstone mass quantification, and molecular analysis. Levels of cholesterol, bile salt, phospholipids, and metabolic parameters in serum and bile were assessed by ELISA. A 3' UTR reporter gene assay was used to verify the direct target genes for miR-146. The relative expression of metabolism genes was analyzed by quantitative real-time PCR and immunoblotting. Results: miR-146a-5p expression was reduced in mice and clinical samples with gallstones. Anta-146 treatment effectively prevented LD-induced gallstone formation in mice without hepatic and cholecystic damage. The mice treated with anta-146 exhibited beneficial alterations in bile cholesterol and bile acids and lipid levels in the blood. A key biliary cholesterol transporter-Megalin was identified as a direct target of miR-146. Anta-146 administration upregulated megalin expression, thereby ameliorating impaired gallbladder cholesterol absorption associated with the LXR-megalin/cubilin pathway. Conclusion: The data demonstrates that miR-146 modulates gallbladder cholesterol absorption by targeting megalin, and prevents the pathogenesis of cholesterol gallstones.

Portable and Recyclable Luminescent Lanthanide Coordination Polymer Film Sensors for Adenosine Triphosphate in Urine.

Adenosine triphosphate (ATP) is a small molecule that is released to the urine from bladder urothelial cells and the bladder mucosal band of the human body. In certain cases, ATP can serve as a biomarker in bladder disease. For the practical applicability of luminescent sensors for ATP in urine, it is significant to find a new strategy for making the detection progress simple and available for in-field urine analysis. Here, a novel luminescent lanthanide coordination polymer (Tb-BPA) was designed and synthesized for quick and sensitive detection of ATP through luminescence quenching with a quenching constant of 4.90 × 103 M-1 and a detection limit of 0.55 × 10-6 M. Besides, Tb-BPA has excellent anti-interference ability and can detect ATP in simulated urine with a small relative standard deviation (<4%). Moreover, the luminescent polyacrylonitrile nanofiber films modified by Tb-BPA were prepared by electrospinning and were used for ATP visual detection. Notably, this film is easy to recover and reuse, and maintains good detection performance after at least 7 cycles.

Highly sensitive sensing of DPA by lanthanide metal-organic frameworks and detection of fiber membranes.

The detection of 2,6-pyridinecarboxylic acid (DPA), as a biomarker of Bacillus anthracis, has attracted wide attention. In previous reports of DPA detection, fluorescent probes may not have high specificity. Therefore, the rational design and development of fluorescent sensors with excellent performance is of great significance for the detection of DPA. In this study, two novel lanthanide metal-organic frameworks (Ln-MOFs) were synthesized by hydrothermal method using 3-polyfluorobiphenyl-3 ', 4,5 ' -tricarboxylic acid (H2FPTA) as ligand. Studies have shown that Ln-MOFs can detect DPA in real time, with detection limits of 0.54 µM and 0.67 µM, respectively, and have a high recovery rate (95 % -108 %) in fetal bovine serum. As a self-calibration sensor, other substances in the blood can be clearly distinguished by a two-dimensional fluorescence code diagram. After the Ln-MOFs were spun into nanofiber membranes, they responded quickly to DPA. This increases practicability and provides a promising idea for the development of simple and efficient ratio sensors.

Nanoarchitectonics of Indocyanine Green/Doxorubicin-Loaded Hydroxyl Boron Nitride Nanosheets for Chemophotothermal Therapy.

Biocompatible hydroxylated boron nitride nanosheets were effectively loaded with indocyanine green and doxorubicin using successive assembly. The indocyanine green/doxorubicin-loaded hydroxyl boron nitride nanosheets (ICG/DOX@OH-BNNS) integrated photothermal therapy and chemotherapy into a single nano vehicle. It had been confirmed that ICG/DOX@OH-BNNS could produce reactive oxygen species and exhibit excellent photothermal effects and light-triggered faster DOX release with NIR laser irradiation. On the other hand, the fluorescence of DOX in ICG/DOX@OH-BNNS was also used for visualizing subcellular location. Compared with individual chemotherapy and photothermal therapy, the combined treatment of ICG/DOX@OH-BNNS could synergistically induce the apoptosis and death of A549 cells and suppress S180 tumor growth in vivo.

Two novel zinc-based MOFs as luminescence sensors to detect phenylglyoxylic acid.

Automobile exhaust gases, plastic pollutants, smoking, and other harmful substances can cause serious harm to human beings and the environment. Styrene, as a common airborne toxin, enters the human body through breathing or the skin and is discharged in the form of phenylglyoxylic acid (PGA). Therefore, specific, sensitive and trace detection of PGA is particularly important. Here, two zinc-based metal-organic frameworks {[Zn2L1(DMF)2H2O](DMF)2H2O}n, {[Zn4(L2)2(DMF)2(H2O)3](DMF)8}n (L1 = 2,5-bis((3-carboxylphenyl)amino)terephthalic acid, L2 = 2,5-bis((4-carboxyphenyl)amino)terephthalic acid) have been reported as 1 and 2, respectively. Both 1 and 2 present 3D structures, which can both be simplified as 4,4,4-c net topology. It is worth mentioning that 2 has two different kinds of Zn SBUs as connecting nodes in the structure. Besides, compared with the other materials for the detection of PGA, 1 and 2 exhibit relatively low detection limits (LODs), both in water and in urine (where the LODs for 1 in water and urine were 0.33 µM and 0.43 µM in the range of 0-0.39 mM, and those for 2 were 0.28 µM and 0.49 µM in the range of 0-0.59 mM, respectively). In addition, the sensors have excellent anti-interference ability, high stability, rapid response, and can easily distinguish between different concentrations of PGA with the naked eye. The developed paper probes were suitable for practical sensing applications for portable detection of PGA in urine.

Two new lanthanide complexes with 5-(Pyrazol-1-yl)nicotinic acid: Structures and their anti-cancer properties.

Two new lanthanide complexes [PrL2(EA)2]NO3 (complex 1) and [SmL2(EA)2]NO3 (complex 2) (H2L = 5-(Pyrazol-1-yl)nicotinic acid, EA = CH3CH2OH) were synthesized. The structures were characterized by single crystal X-ray and elemental analysis. The interaction between the complex and fish sperm DNA(FS-DNA) was monitored using ultraviolet and fluorescence spectroscopy, and the binding constants were determined. Both complexes showed the ability to effectively bind DNA, and the molecular docking technology was used to simulate the binding of the complex and DNA. In addition, through the annexin V-Fluorescein Isothiocyanate(FITC)/ Propidium Iodide (PI) test experiment, tetrazollium [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) in vitro test, and cell morphology apoptosis studies, it was shown that the complex can effectively induce HeLa tumor cell apoptosis. Compared with cisplatin and complex, complex 1 shows significant cancer cell inhibition, and we hope that this new type of complex will open up new ways for the next generation of drugs in biomedical applications.

Highly Emissive Metal-Organic Frameworks for Sensitive and Selective Detection of Nitrofuran and Quinolone Antibiotics.

The overuse of antibiotics makes its detection very significant for human health. New facile methods and high-performance sensory materials will be urgently needed for detection of antibiotics. Unfortunately, there are few reports on fluorescence enhancement of antibiotics detection. Herein, based on the modulability of the coordination mode, we proposed two MOFs with different coordination modes based on different metal ions: Zn-MOF (1) and Cd-MOF (2). The fluorescence of 1 and 2 can be efficiently and selectively quenched by nitrofuran antibiotics (nitrofurazone, NFZ and furazolidone, FZD) and chloramphenicol (CAP), respectively. Particularly, the matched energy levels between 2 and enrofloxacin (ENR) enables 2 with turn-on sensing for ENR. Moreover, apart from the sensitivity and selectivity, 1 and 2 also have strong recyclable ability, fast response time and anti-interference ability, which make them great potential sensory materials to detect antibiotics.

Three novel metal-organic frameworks with different coordination modes for trace detection of anthrax biomarkers.

Dipicolinic acid (DPA) is an anthrax biomarker. Its serious consequences make its detection a great need. In this paper, three novel metal-organic frameworks (MOFs) with different coordination modes were synthesized by a simple solvothermal method, which can be used as highly efficient fluorescence sensors for the highly selective and sensitive trace detection of DPA. MOFs 1-3 showed rapid responses to DPA (<30 s), and the limits of detection (LODs) were calculated to be 1.01 × 10-6 M-1 (MOF 1), 1.17 × 10-6 M-1 (MOF 2) and 2.07 × 10-6 M-1 (MOF 3). DPA detection based on MOFs 1-3 in fetal bovine serum is highly reliable based on the high recovery rates (90% to 115%). Hence, the three MOF-based sensors can be used in the real-time detection of DPA.

Multicenter Metal-Organic Framework-Based Ratiometric Fluorescent Sensors.

Metal-organic frameworks (MOFs) with multiple emission centers are newly emerging as ratiometric sensors owing to their high sensitivity and high selectivity toward a wide range of targeted functional species. Energy transfer between the light-absorbing group and emission centers and between different emission centers is the key to rationally design and synthesize MOF-based ratiometric sensors. A good match between the energy levels of the light-absorbing groups and emission centers is the prerequisite for MOF-based sensors to exhibit multiple emissions, and a good match of the MOF-based sensors and those of the targeted species can increase the sensitivity and selectivity, but this match is highly challenging to obtain via synthesis. MOFs with multiple emission centers can be produced by functionalizing MOFs with multiple lanthanide centers, organic luminophores, dyes, carbon dots, and other such emissive groups. In this progress report, recent advances in the strategies for synthesizing MOFs with multiple emission centers and their applications for ratiometric sensing of solution conditions, including the pH value, and ion, organic molecule, and biomolecule concentrations, are summarized, as are the related sensing mechanisms.