Eight isostructural lanthanide coordination polymers [Ln(bptc)(phen)(H2O)]n (Ln = Dy for , Eu for , Tb for , Gd for , Sm for , Nd for , Yb for , Pr for ) were successfully prepared based on bridging asymmetric polycarboxylate ligand biphenyl-3,2',5'-tricarboxylic acid (H3bptc) and chelating 1,10-phenanthroline (phen) coligand. Single crystal X-ray analysis reveals that complexes have a (3,6)-connected CdI2-type coordination network consisting of paddle-wheel dimers [Ln2(CO2)4]. The magnetic and fluorescent properties of have been investigated. Significantly, the Dy(iii) complex behaves with slow relaxation of the magnetization, where the frequency-dependent out-of-phase signals are noticed.

As the energy source of living cells and the intermediate product of metabolism, glucose plays an important role in biological systems. Therefore, it is of great significance to establish a reliable and sensitive method for the detection of glucose, especially in blood. Herein, a “switch-on” fluorescence sensor for rapid, sensitive, and specific detection of glucose was successfully developed. In this strategy, PCN-224 served as the recognition unit, while AgNPs played the roles as both a “quencher”, to decrease the fluorescence intensity of PCN-224, and an H2O2 recognizer. After exposure to H2O2 that was produced in situ during GO x -catalyzed oxidation of glucose, AgNPs can be effectively etched into silver ions and released from PCN-224, thereby recovering the fluorescence of PCN-224. The present sensing strategy shows many merits including high sensitivity with a low limit of detection (0.078 μM) and excellent selectivity toward glucose over other saccharides. More importantly, the sensing platform we proposed was further extended to monitoring glucose in human serum samples with satisfactory recoveries, indicating its promising potential for diagnostic purposes.

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Use of hydrocarbon fuels as coolants for future high-Mach aircraft is challenged by the formation of carbonaceous deposits during thermal stressing at high temperatures (>500 °C). Three hydrogen donors, tetralin (THN), R-tetralone (THNone), and benzyl alcohol (BzOH), and two organic selenides, diphenyl selenide (Ph 2 Se) and diphenyl diselenide (Ph 2 Se 2 ), as well as their mixtures, are selected as thermally stable additives to inhibit the deposition from the thermal stressing of n-dodecane and Chinese RP-3 (No. 3 jet fuel). It is found that the amount of solid deposits from thermal stressing of RP-3 is reduced by 77.0% with the additive of Ph 2 Se 2 /THN/THNone. The carbonaceous solid is further characterized using temperature-programmed oxidation (TPO), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). It is revealed that hydrogen donor THN/THNone and organic selenides possibly reduce the carbon deposits through retarding the thermal cracking rate, blocking surface catalysis, and depressing reactivity of sulfur with the surface metals, as well as their synergistic effect. The morphologies of deposits also dramatically change after adding organic selenides or hydrogen donors.

The nonspecific biodistribution of cytotoxic drugs and associated adverse effects greatly limit the efficacy and patient compliance of chemotherapy. To address this, we employed a photoswitchable microtubule inhibitor (Azo-CA4) that was physically loaded in cyclodextrin-bearing micellar nanocarriers through the host-guest interaction. Azo-CA4 was only activated upon ultraviolet (UV) light irradiation to trigger the transition from the "trans" (inactive) to "cis" (active) state. Such conformation change could then induce rapid Azo-CA4 release from micelles without the delay of the onset of therapeutic action. This nanoscale delivery system produced photo-triggered antimitotic and pro-apoptotic effects in MDA-MB-231 cells via a triggered control of microtubule dynamics. The anticancer efficacy of Azo-CA4-loaded micelles was further proved in vivo using a 4T1 tumor-bearing mice model coupled with multiple topical administrations to avoid the penetration problem of UV light. This work provides a new delivery vehicle to aid the application and potential translation of Azo-CA4 as biomedical tools and precision chemotherapeutics.

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Highly selective thin zeolite MFI membranes are synthesized on porous stainless steel and α-alumina supports using a seeded growth method. An ultraviolet (UV) light treatment is employed as a low temperature alternative to remove the organic structure-directing agent (SDA) to avoid membrane cracking. The feasibility of the use of the MFI membranes as an explosive preconcentrator is examined by measuring the permeation of nitrogen (N(2), an air surrogate) and 1,3,5-trimethylbenzene (TMB) (a 2,4,6-trinitrotoluene (TNT) surrogate) in a mixture of N(2) and TMB. High N(2)/TMB selectivity (>10,000) and reasonable N(2) flux (13.5 mmol/m(2)·s) are observed. On the basis of the flux, a hollow fiber array based preconcentrator is proposed and estimated to provide 1000× concentration within about 1 min using a hollow fiber with a 50 μm internal radius. This high performance explosive preconcentrator may open a new venue for the detection of subppb or lower level of explosives simply in conjunction with conventional explosives detectors.