Disease Progression in Patients With Nontuberculous Mycobacterial Lung Disease of Nodular Bronchiectatic (NB) Pattern: The Roles of Cavitary NB and Soluble Programmed Death Protein-1.

BACKGROUND: In patients with nodular bronchiectatic (NB) nontuberculous mycobacterial lung disease (NTM-LD), risk factors for disease progression have not been clearly investigated. The roles of cavitary NB and soluble programmed death protein-1 (sPD-1), an immune-related biomarker, in the disease course of NB NTM-LD remain unknown. METHODS: Patients with NB NTM-LD were enrolled from 2 medical centers in 2014-2020. We identified cavitary NB, measured sPD-1 levels, and analyzed factors associated with cavitary NB and predictors for disease progression of NB NTM-LD. RESULTS: Of 120 cases of NB NTM-LD, 87 (72.5%) were caused by Mycobacterium avium complex. sPD-1 levels were lower in 13 (10.8%) patients with cavitary NB than in noncavitary patients (P = .020). Over 1.41 ± 1.43 years of follow-up, 12 (92.3%) patients in the cavitary and 66 (61.7%) in the noncavitary group developed disease progression (P = .032). In multivariable analysis, body mass index (BMI [kg/m2]; adjusted hazard ratio [aHR], .895 [95% confidence interval, .811-.988]), sputum smear grade (aHR, 1.247 [1.014-1.534]), cavitary NB (aHR, 2.008 [1.052-3.834]), and sPD-1 (per 10-pg/mL increase; aHR, .889 [.816-.967]) were predictive for disease progression. Notably, sPD-1 showed a dose-dependent association with disease progression (sPD-1 ≤23.5 pg/mL; aHR, 3.306 [1.664-6.567]; sPD-1: 23.6-53.7 pg/mL; aHR, 2.496 [1.390-4.483]) compared with the reference (sPD-1 >53.7 pg/mL). CONCLUSIONS: Patients with NB NTM-LD and low sPD-1, low BMI, high smear grade, and cavitary NB were at high risk for disease progression. sPD-1 was low in patients with cavitary NB phenotype and dose-responsively associated with disease progression.

Using an ATR-FTIR Technique to Detect Pathogens in Patients with Urinary Tract Infections: A Pilot Study.

Urinary tract infections (UTIs) are a leading hospital-acquired infection. Although timely detection of causative pathogens of UTIs is important, rapid and accurate measures assisting UTI diagnosis and bacterial determination are poorly developed. By reading infrared spectra of urine samples, Fourier-transform infrared spectroscopy (FTIR) may help detect urine compounds, but its role in UTI diagnosis remains uncertain. In this pilot study, we proposed a characterization method in attenuated total reflection (ATR)-FTIR spectra to evaluate urine samples and assessed the correlation between ATR-FTIR patterns, UTI diagnosis, and causative pathogens. We enrolled patients with a catheter-associated UTI in a subacute-care unit and non-UTI controls (total n = 18), and used urine culture to confirm the causative pathogens of the UTIs. In the ATR-FTIR analysis, the spectral variation between the UTI group and non-UTI, as well as that between various pathogens, was found in a range of 1800-900 cm-1, referring to the presence of specific constituents of the bacterial cell wall. The results indicated that the relative ratios between different area zones of vibration, as well as multivariate analysis, can be used as a clue to discriminate between UTI and non-UTI, as well as different causative pathogens of UTIs. This warrants a further large-scale study to validate the findings of this pilot research.

The distinct O2 quenching mechanism between fluorescence and phosphorescence for dyes adsorbed on silica gel.

We herein aim to probe the emission quenched by O2 on silica gel. Our special focus is on the O2 quenching of the fluorescence of a series of organic D-π-A phosphonium compounds 1-3. The results show that the O2 quenching rate constants for the fluorescence of 1-3 are on the order of 1010 M-1 s-1, which are nearly on the same order as those measured for 1-3 and common organic compounds in solution. In yet another approach, the study of O2 quenching of phosphorescence in the solid phase indicates that the O2 quenching rate constant for the triplet state, i.e., , is smaller than by two orders of magnitude. Detailed investigation indicates that this distinction stems from the intrinsic O2 quenching rate constants for the singlet and triplet states subsequent to the formation of collisional complexes. In the absence of the solvent cage effect, is greatly influenced by the formation energy of the O2-dye CT complex, whereas in the solid phase is a nearly diffusion-controlled rate. Due to the larger distinction between and in the solid phase, O2 quenching of fluorescence is efficient for dyes in the solid phase. This leads to a feasible application of sensing O2 with regular fluorescent dyes adsorbed on porous solid substrates.

Silver Nanoplates for Colorimetric Determination of Xanthine in Human Plasma and in Fish Meat via Etching/Aggregation/Fusion Steps.

Silver nanoplates (AgP) were prepared and used in a colorimetric method for the evaluation of Xanthine (Xan) in blood plasma and fish meat. The detection mechanism for Xan was observed to occur via etching of AgP particles/aggregation/fusion steps, resulting in a color change from blue to grey. First, the basic Xan solution is adsorbed through partial substitution of capping molecules around the AgP with Xan, and then intermolecular hydrogen bonds form between AgP and AgP. Subsequently, the titrant Xan solution further etches the AgP and finally fuses particles together. Owing to the step by step mechanism, the response range towards Xan has two linear regression ranges: 0.15-0.60 µM and 0.61-3.00 µM, respectively. The detection limit in the range of 0.15-0.60 µM is 0.011 µM (S/N = 3). AgP exhibits good selectivity for Xan over other potential interferents such as amino acids and blood proteins. AgP achieves rapid detection of Xan and can be applied to the satisfactory determination of Xan in blood plasma and fish meat. This colorimetric sensor is easy to use, cost effective, fast, selective and user friendly.

Luminescent Triphosphine Cyanide d(10) Metal Complexes.

Coinage metal cyanides efficiently react with a triphosphine. PPh2C6H4-PPh-C6H4PPh2 (P(3)). to give the complexes M(P(3))CN, where M = Cu (1), Ag (2), and Au (3), which can further interact with coordinatively unsaturated metal centers [M(P(3))](+) to give the homobimetallic [(P(3))M-CN-M(P(3))](+)X(-) [M = Cu (4a with X(-) = CF3SO3(-) and 4b with X(-) = BF4(-)), Ag (5)] or heterometallic [(P(3))Au-CN-Ag(P(3))](+) (6) species. Extension of this approach also provided the trinuclear complex [(P(3))Cu-NC-Au-CN-Cu(P(3))](+) (7). Compounds 1-5 were characterized in the solid state by X-ray crystallography. The NMR spectroscopic studies revealed that all of the complexes except 6 retain their structures in solution. The title compounds are luminescent in the solid state, with quantum yields ranging from 8 to 87%. The observed photoemission originates mainly from the metal-to-ligand charge-transfer states according to time-dependent density functional theory computational studies. The crystalline bimetallic Cu complexes 4a/4b demonstrate extremely high sensitivity of the emission intensity to molecular O2 (KSV1 = 639 atm(-1) and LOD = 0.010% for 3 times the signal-to-noise ratio).

Predicting stringent QuantiFERON-TB Gold Plus conversions in contacts of tuberculosis patients.

OBJECTIVES: To assess associations between disease severity in index TB patients and QuantiFERON-TB Gold Plus (QFT-Plus) results in contacts, and predictors for QFT-Plus conversion in contacts over 6-12 months. METHODS: TB patients (n = 295) and the contacts (n = 1051) were enrolled during 2018-2021 with QFT-Plus performed at baseline and months 6 and 12. A strong CD8 response was defined as TB2 interferon gamma (IFN-γ) response minus TB1 >0.6 IU/ml and stringent conversion as change from QFT-plus negative to high-positive QFT-Plus (TB1 or TB2 IFN-γ responses >0.7 IU/ml). RESULTS: Contacts with index TB patients with sputum smear >1+ was associated with positive QFT-Plus compared to those without (p < 0.001). Contacts with index TB patients with bilateral lung disease were more likely to have strong CD8 responses than those without (p = 0.038). QFT-Plus stringent conversion occurred in 9.7% of contacts over 6-12 months. A TB1 IFN-γ response ≥0.03 IU/ml combined with a TB2 ≥0.06 IU/ml was predictive of a 19-fold increased risk for QFT-Plus stringent conversion in contacts (odd ratio 19.565 [8.484-45.116], p < 0.001). CONCLUSION: Bacterial burden and bilateral lung disease of index TB patients were associated with positive QFT-Plus and strong CD8 responses in contacts. TB1 and TB2 IFN-γ responses were synergistically predictive of stringent conversion in contacts.

Glucose Sensing in Human Whole Blood Based on Near-Infrared Phosphors and Outlier Treatment with the Programming Language "R".

A near-infrared paper-based analytical device (NIR-PAD) for glucose detection in whole blood was based on iridium(III) metal complexes embedded in a three-dimensional (3D) enzyme gel. These complexes emit NIR luminescence, can avoid interference from the color of blood, and increase the sensitivity of sensing glucose. The glucose reaction behaviors of another two different iridium(III) and platinum(II) complexes were also tested. When the glucose solution was added to the device, the oxidation of glucose by glucose oxidase caused oxygen consumption and increased the intensity of the phosphorescence emission. To the best of our knowledge, this is the first time that data have been treated with the programming language "R", which uses Tukey's test to identify the outliers in the data and calculate a median for establishing a calibration curve, in order to improve the accuracy of NIR-PADs for sensing glucose. Compared with other published devices, NIR-PADs exhibit a wider linear range (1-30 mM, [relative emission intensity] = 0.0250[glucose] + 0.0451, and R 2 = 0.9984), a low detection limit (0.7 mM), a short response time (<2 s), and a small sample volume (2 µL). Finally, blood specimens were obtained from 19 patients enrolled in Taipei Veterans General Hospital under an approved IRB protocol (Taiwan; 2017-12-002CC). The sensors exhibited remarkable characteristics for glucose detection in comparison with other methods, including the clinical method in hospitals as well as those without blood sample pretreatment or a dilution factor. The above results confirm that NIR-PAD sensors can be put to practical use for glucose detection.

Circulating mitochondrial cell-free DNA dynamics in patients with mycobacterial pulmonary infections: Potential for a novel biomarker of disease.

Objectives: Human mitochondrial cell-free DNA (Mt-cfDNA) may serve as a useful biomarker for infectious processes. We investigated Mt-cfDNA dynamics in patients with pulmonary mycobacterial infections to determine if this novel biomarker could be used to differentiate disease states and severity. Methods: Patients with pulmonary tuberculosis (PTB), latent tuberculosis infection (LTBI), and nontuberculous mycobacterial-lung disease (NTM-LD) were enrolled at a tertiary care hospital in Taiwan between June 2018 and August 2021. Human Mt-cfDNA and nuclear-cfDNA (Nu-cfDNA) copy numbers were estimated by quantitative polymerase chain reaction. Variables associated with PTB and 2-month sputum culture-positivity, indicating poor treatment response, were assessed using logistic regression. Results: Among 97 patients with PTB, 64 with LTBI, and 51 with NTM-LD, Mt-cfDNA levels were higher in patients with PTB than in LTBI (p=0.001) or NTM-LD (p=0.006). In the Mycobacterium tuberculosis-infected population, Mt-cfDNA levels were highest in smear-positive PTB patients, followed by smear-negative PTB (p<0.001), and were lowest in LTBI persons (p=0.009). A Mt-cfDNA, but not Nu-cfDNA, level higher than the median helped differentiate culture-positive PTB from culture-negative PTB and LTBI (adjusted OR 2.430 [95% CI 1.139-5.186], p=0.022) and differentiate PTB from NTM-LD (adjusted OR 4.007 [1.382-12.031], p=0.011). Mt-cfDNA levels decreased after 2 months of treatment in PTB patients (p=0.010). A cutoff Mt-cfDNA level greater than 62.62 x 106 copies/µL-plasma was associated with a 10-fold risk of 2-month culture-positivity (adjusted OR 9.691 [1.046-89.813], p=0.046). Conclusion: Elevated Mt-cfDNA levels were associated with PTB disease and failed sputum conversion at 2 months in PTB patients, and decreased after treatment.

A new coordination polymer exhibiting unique 2D hydrogen-bonded (H2O)16 ring formation and water-dependent luminescence properties.

A new coordination polymer, [Zn(dpe)(bdc)]·4H(2)O (ZndB; dpe=1,2-bis(4-pyridyl)ethane, bdc(2-)=dianion of benzenedicarboxylic acid), which possesses a 3D metal-organic framework (MOF) has been synthesized and structurally characterized. This 3D MOF is constructed by the assembly of helical channels filled with guest water molecules in both inner and outer regions of the channel. The resulting network also creates a 2D water layer containing hydrogen-bonded (H(2)O)(16) rings as the basic building units. Thermogravimetric and powder X-ray diffraction measurements of ZndB revealed a two-step weight loss of water molecules with a reversible water adsorption/desorption process in the inner channel for the first stage, and irreversible water desorption in the outer channel for the second stage. This spongelike property is manifested by the excimer emission originating from interaction between dpe (π*) and the other dpe (π) of the proximal helical channel, which is highly sensitive to the environmental perturbation. Powder X-ray analyses reveal that the dehydration process induces the readjustment of dpe π-π stacking distance/orientation, which results in dramatic luminescence changes from dim pale blue (λ(em)≈470 nm) upon hydration to bright white-light generation (broad, λ(em)≈500-550 nm) upon water depletion, accompanied by a ≈100-fold increase in the emission intensity.

Reversible solid-state structural transformation of a 1D-2D coordination polymer by thermal De/rehydration processes.

A new coordination polymer, [Zn(HBTC)(BPE)0.5(H2O)]n·nH2O (1) with an extended 1D ladderlike metal-organic framework (MOF) has been synthesized and structural characterized by single-crystal X-ray diffraction method. Structural determination reveals that, in compound 1, the Zn(II) ion is four-coordinated in a distorted tetrahedral geometry, bonded to one nitrogen atom from one BPE ligand, and three oxygen atoms from two monodentate carboxylate groups of two HBTC(2-) ligands and one coordinated water molecule. The HBTC(2-) acts as a bridging ligand with a bis-monodentate coordination mode, connecting the Zn(II) ions to form a one-dimensional (1D) [Zn(HBTC)] chain. Two 1D chains are then interlinked via the connectivity between the Zn(II) ions and anti-BPE liagnds to complete the 1D ladderlike MOF. Adjacent 1D Ladders are further extended to a 2D hydrogen-bonded layered network through the intermolecular O-H · · · O hydrogen bond between the carboxylic group and carboxylate group of interladder HBTC(2-) ligand. Adjacent 2D layers are then packed orderly in an ABAB-type array via the intermolecular interactions of combined π-π interaction and O-H · · · O hydrogen bonds to form a 3D supramolecular architecture exhibiting 1D channels intercalated with guest water molecules. The reversible solid-state structural transformation between crystalline 1 with 1D ladderlike framework and its dehydrated powder 2, [Zn(HBTC)(BPE)0.5]n, with 2D framework via the displacement of coordinated water molecule to HBTC(2-) ligand, by thermal de/rehydrated processes has been verified by PXRD measurements. The emission of 1 and 2 is ascribed to a ligand-based transition.

Quantitative urinary tract infection diagnosis of leukocyte esterase with a microfluidic paper-based device.

Leukocyte esterase (LE) is a useful marker that can be used in establishing a diagnosis of urinary tract infections (UTIs). The development of a UTI diagnostic method with quantitative determinations of biomarkers across all age groups is becoming more important. In this report, microfluidic resistance sensors based on silver ink (Ag ink) and silver ink mixed with ZnO nanoparticles (Ag-ZnO ink) were synthesized and coated on cellulose paper, namely LE-Ag-µPADs and LE-Ag-ZnO-µPADs, respectively, for the sensitive detection of LE. The microfluidic design increases the precision of data and further allows for quantitative determination and early detection of LE in human urine. The quantification of LE relies on the change in the resistance readout coating with Ag ink as well as Ag-ZnO ink in the detection zone. A mixture of 3-(N-tosyl-l-alaninyloxy)-5-phenylpyrrole (PE) and 1-diazo-2-naphthol-4-sulfonic acid (DAS) was deposited in the sample zone to selectively recognize LE, and the resulting nonconductive products, i.e., azo compounds, further reacted with the Ag ink and Ag-ZnO ink to increase resistance. The quantitative detectable LE concentrations between 2 to 32 (×5.2 U mL-1), i.e. ≈12 to 108 µg L-1, cover the commercial dipstick range of trace, +1 and +2. The minimum detectable concentration of LE in urine was 1 (×5.2 U mL-1). The lower concentrations of LE detectable by LE-Ag-µPADs (1-8 × 5.2 U mL-1) are below the value achieved with the ELISA LE kit. Urine samples from inpatients with indwelling urinary catheters were used, and the LE levels measured by the present device were highly correlated with those determined by a commercial urine analyser.

Photoisomerization of a maleonitrile-type salen Schiff base and its application in fine-tuning infinite coordination polymers.

Strategically designed salen ligand 2,3-bis[4-(di-p-tolylamino)-2-hydroxybenzylideneamino]maleonitrile (1), which has pronounced excited-state charge-transfer properties, shows a previously unrecognized form of photoisomerization. On electronic excitation (denoted by an asterisk), 1Z*-->1E isomerization takes place by rotation about the C2--C3 bond, which takes on single-bond character due to the charge-transfer reaction. The isomerization takes place nonadiabatically from the excited-state (1Z) to the ground-state (1E) potential-energy surface in the singlet manifold; 1Z and 1E are neither thermally inconvertible at ambient temperature (25-30 degrees C), nor does photoinduced reverse 1E*-->1Z (or 1Z*) isomerization occur. Isomers 1Z and 1E show very different coordination chemistry towards a Zn(II) precursor. More prominent coordination chemistry is evidenced by a derivative of 1 bearing a carboxyl group, namely, N,N'-dicyanoethenebis(salicylideneimine)dicarboxylic acid (2). Applying 2Z and its photoinduced isomer 2E as building blocks, we then demonstrate remarkable differences in morphology (sphere- and needlelike nanostructure, respectively) of their infinite coordination polymers with Zn(II).

Highly emissive cyclometalated rhenium metallacycles: structure-luminescence relationship.

We report on a series of new self-assembled cyclometalated dirhenium(I) metallacyclic complexes via an unprecedented rhenium-mediated C-H bond activation and the relationship between their structures and luminescence properties.

Quantitative determination of leukocyte esterase with a paper-based device.

The commercially-available colorimetric urine dipstic for the early detection of urinary tract infection (UTI) has several limitations. The quantitative determination of urinary leukocyte esterase (LE) for predicting UTI remains uncertain. This study presents a paper-based analytical device to detect LE (LE-PAD) as a point-of-care quantitative test for UTI. The LE-PAD is composed of a coating of mixed 3-(N-tosyl-L-alaninyloxy)-5-phenylpyrrole (PE) and 1-diazo-2-naphthol-4-sulfonic acid (DAS) deposited onto a silver conducting film (Ag film). The LE/urine reacts with the PE and DAS, and the resulting products in turn react with the silver coating, causing a change in resistivity. The quantitative calibration curve was established in this study and has been used to analyse urine samples from inpatients with urinary catheters (n = 21). The results revealed that the level of LE determined by LE-PADs was predictive of UTI diagnosis with an area under the receiver operating characteristic curve of 0.875 (95% confidence interval, 0.704-1.000). Using an appropriate cut-off value, the sensitivity and specificity of UTI diagnosis by LE-PAD were 87.5% and 92.3%, while the LE-positivities of urine dipstics were 62.5% and 76.9%, respectively. For UTI diagnosis, the LE-PAD demonstrated positive and negative likelihood ratios of 11.38 and 0.14, suggesting that the novel LE-PAD is a reliable test.

Mercury(II) recognition and fluorescence imaging in vitro through a 3D-complexation structure.

8,8'-(1,4,10,13-Tetrathia-7,16-diazacyclooctadecane-7,16-diyl)-bis(methylene)diquinolin-7-ol (TTBQ) was synthesized and proved to selectively recognize Hg(2+), forming a Hg(2+)/TTBQ complex with an association constant (K(a)) as large as approximately 1.3 x 10(4) +/- 520 M(-1) in aqueous solution. Single crystals of TTBQ and a TTBQ-Hg(2+) complex have also been successfully grown, in which the latter unambiguously revealed a cagelike configuration consisting of thiol-crown and dual 7-hydroxyquinoline moieties to firmly trap Hg(2+). This 3D-complexation structure accounts for approximately 25-fold luminescence enhancement and a detection limit of sub-microM in water for sensing Hg(2+). Great selectivity toward Hg(2+) has been exhibited over alkali- and alkaline-earth metal ions, first-row transition-metal ions, and other cations studied. This chemosensor is particularly suited for the detection of Hg(2+) in a pH range of 5.5 to 7.5. This, in combination with its fine biocompatibility, leads to the success toward in vitro mercury recognition based on fluorescence imaging.

Synthesis, Structural Characterization and Ligand-Enhanced Photo-Induced Color-Changing Behavior of Two Hydrogen-Bonded Ho(III)-Squarate Supramolecular Compounds.

Two coordination polymers (CPs) with chemical formulas, [Ho2(C4O4)2(C2O4)(H2O)8]·4H2O (1) and [Ho(C4O4)1.5(H2O)3] (2), (C4O42- = dianion of squaric acid, C2O42- = oxalate), have been synthesized and their structures were determined by single-crystal X-ray diffractometer (XRD). In compound 1, the coordination environment of Ho(III) ion is eight-coordinate bonded to eight oxygen atoms from two squarate, one oxalate ligands and four water molecules. The squarates and oxalates both act as bridging ligands with 1,2-bis-monodentate and bis-chelating coordination modes, respectively, connecting the Ho(III) ions to form a one-dimensional (1D) ladder-like framework. Adjacent ladders are interlinked via O-HO hydrogen bonding interaction to form a hydrogen-bonded two-dimensional (2D) layered framework and then arranged orderly in an AAA manner to construct its three-dimensional (3D) supramolecular architecture. In compound 2, the coordination geometry of Ho(III) is square-antiprismatic eight coordinate bonded to eight oxygen atoms from five squarate ligands and three water molecules. The squarates act as bridging ligands with two coordination modes, 1,2,3-trismonodentate and 1,2-bis-monodentate, connecting the Ho(III) ions to form a 2D bi-layered framework. Adjacent 2D frameworks are then parallel stacked in an AAA manner to construct its 3D supramolecular architecture. Hydrogen bonding interactions between the squarate ligands and coordinated water molecules in 1 and 2 both play important roles on the construction of their 3D supramolecular assembly. Compounds 1 and 2 both show remarkable ligand-enhanced photo-induced color-changing behavior, with their pink crystals immediately turning to yellow crystals under UV light illumination.

Paper-based microfluidic devices based on 3D network polymer hydrogel for the determination of glucose in human whole blood.

In this study, optical microfluidic paper analytical devices (µPADs) for glucose detection from whole blood samples with a small sample volume (2 µL) have been developed on a single paper. In the proposed method, a mushroom-shaped analytical device contains a sample inlet zone and a detection zone. When blood is dripped onto the inlet region of a µPAD, the plasma diffuses to the detection region. The detection region is implanted with a metallic three-dimensional (3D) polymer hydrogel vehicle. The gel vehicle consists of a copper complex that responds to oxygen changes and glucose oxidase (GOx) immobilized inside the gel as a bioactivity preservative. The phosphorescence of the copper complex is enhanced by oxygen consumed by detection of glucose with a limit of detection (S/N = 3) of 0.44 mM, and the total analysis of the sample is completed within 1 min. The validity of the proposed research is demonstrated using control samples and real-world whole blood samples of glucose concentrations ranging from 3 to 200 mM, and the detection results are shown to be in agreement with those obtained using a glucometer. Attaining a simple device for analysing glucose in human whole blood without any pretreatment procedures and having a broad sensing range while consuming a small sample volume remain challenging; thus, our new analytical device is of great interest.

Excited-state double proton transfer in model base pairs: the stepwise reaction on the heterodimer of 7-azaindole analogues.

A four fused-ring system 11-propyl-6H-indolo[2,3-b]quinoline (6 HIQ) is strategically designed and synthesized; it possesses a central moiety of 7-azaindole (7AI) and undergoes excited-state double proton transfer (ESDPT). Despite a barrierless type of ESDPT in the 6 HIQ dimer, femtosecond dynamics and a kinetic isotope effect provide indications for a stepwise ESDPT process in the 6 HIQ/7AI heterodimer, in which 6 HIQ (deuterated 6 HIQ) delivers the pyrrolyl proton (deuteron) to 7AI (deuterated 7AI) in less than 150 fs, forming an intermediate with a charge-transfer-like ion pair, followed by the transfer of a pyrrolyl proton (deuteron) from cation-like 7AI (deuterated 7AI) to the pyridinyl nitrogen of the anion-like 6 HIQ (deuterated 6 HIQ) in approximately 1.5+/-0.3 ps (3.5+/-0.3 ps). The barrier of second proton transfer is estimated to be 2.86 kcal mol(-1) for the 6 HIQ/7AI heterodimer.

New supramolecular isomers with 2D 4(4) square-grid and 3D 6(5).8 frameworks in a one-pot synthesis; reversible solvent uptake and intriguing luminescence properties.

Two supramolecular isomers of [Ni(4-bpd)(2)(NCS)(2)] (4-bpd = 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene) with 2D 4(4) square-grid and 3D 6(5).8 frameworks are co-crystallized in a one-pot reaction, both of which exhibit interesting luminescence properties and reversible adsorption-desorption with respect to guest solvents.

Diaza-18-crown-6 appended dual 7-hydroxyquinolines; mercury ion recognition in aqueous solution.

8,8'-(1,4,10,13-Tetraoxa-7,16-diazacyclooctadecane-7,16-diyl)bis(methylene)diquinolin-7-ol (TDBQ) was synthesized and proved to recognize Hg2+ via reducing Hg2+ to Hg+, forming a unique Hg(2)2+ - complex.