A V-shaped bis-coumarin based fluorescence probe for F- detection in tea infusions and potable water and bioimaging applications in living systems.

Fluorine (F) is a pivotal element in the formation of human dental and skeletal tissues, and the consumption of water and tea constitutes a significant source of fluoride intake. However, prolonged ingestion of water and tea with excessive fluoride content can lead to fluorosis, which poses a serious health hazard. In this manuscript, a novel turn-on fluorescent probe DCF synthesized by bis-coumarin and tert-butyldiphenylsilane (TBDPS) was introduced for detecting F- in potable water and tea infusions. By leveraging the unique chemical affinity between fluoride and silicon, F- triggers the silicon-oxygen bond cleavage in DCF, culminating in a conspicuous emission of yellow fluorescence. Validated through a succession of optical tests, this probe exhibits remarkable advantages in terms of superior selectivity, a low detection limit, a large Stokes shift, and robust interference resistance when detecting inorganic fluoride. Moreover, it can serve as portable test strips for on-site real-time identification and quantitative analysis of F-. Furthermore, the application of DCF for in-situ monitoring and imaging of F- in zebrafish and soybean root tissues proved its significant value for F- detection in both animal and plant systems. This probe potentially functions as an efficient instrument for delving into the toxic mechanisms of fluoride in physiological processes.

A fluorescent probe for rapid detection of low concentration mercury ions and its application in biological cells.

As a toxic substance, mercury can easily cause harm to organisms and humans. The development of methods that allow rapid detection of low concentrations of mercury ions has a positive effect on the natural environment and human health. The fluorescent probe RBSH reported in this paper has a detection limit as low as 5.9 nM, and a fast response time and allows naked eye detection. We characterized its structure by nuclear magnetic resonance and mass spectrometry, and explored the response mechanism of the probe using Job's plot, and 1H NMR and mass spectrometry. UV-vis spectrophotometry and fluorescence spectroscopy show the excellent optical properties of the probe RBSH. The low toxicity and high cell penetration capacity demonstrated by the cellular assay open up the possibility of biological experiments. By selecting hosts (natural water samples, soybean plants and zebrafish) where mercury ions are likely to be present in the biological chain for low concentration Hg2+ detection, the results all demonstrated the excellent performance of the probe RBSH.

Synergistic Engineering of Conduction Band, Conductivity, and Interface of Bilayered Electron Transport Layers with Scalable TiO2 and SnO2 Nanoparticles for High-Efficiency Stable Perovskite Solar Cells.

A simple, synergistic engineering of the conduction band (CB), conductivity, and interface of TiO2-based bilayered electron transport layers (ETLs) via scalable TiO2 and SnO2 nanoparticles processed at low temperature (≤ 100 °C) for regular planar perovskite solar cells (PSCs) was developed. The bottom layer (Lt-TiO2:SnO2 nanocomposite film) was prepared by spin coating from the ethanol suspension of small ground TiO2 nanoparticles with big ground SnO2 nanoparticles as the additive. The top C-SnO2 layer (spin-coated from the concentrated commercial SnO2 nanoparticles (C-SnO2 NPs, 20 wt %, 7 nm in size suspended in H2O)) can be regarded as an interlayer between Lt-TiO2:SnO2 and perovskite (Psk) absorbers. Bilayered Lt-TiO2:SnO2/C-SnO2 ETLs are dense films with a cascade CB, good conductivity, facile electron extraction/transport ability, and a highly hydrophilic surface for depositing high-quality Psk films. Regular planar PSCs based on Lt-TiO2:SnO2/C-SnO2 ETLs combined with a (FAI)0.90(PbI2)0.94(MABr)0.10(PbBr2)0.10 absorber and a spiro-OMeTAD hole transporter achieved the highest power conversion efficiency of 22.04% with a negligible current hysteresis. The champion cell lost less than 3% of the initial efficiency under continuous room lighting (1000 lux) for 1000 h (lost 10% after 2184 h) without encapsulation under an inert atmosphere. Four related low-temperature-processed ETLs (Lt-TiO2/C-SnO2, Lt-C-SnO2, Lt-TiO2:SnO2, and Lt-TiO2) were fabricated using the same metal oxide nanoparticle suspensions and studied simultaneously to reveal the function of each metal oxide in the bilayered Lt-TiO2:SnO2/C-SnO2 ETLs. In the bottom Lt-TiO2:SnO2 layer, small TiO2 nanoparticles were needed for making a dense film, and highly conducting big SnO2 nanoparticles are used to increase the conductivity of ETLs and a handy electron transport path for reducing the charge accumulation and series resistance of the cell. A top C-SnO2 layer (regarded as an interlayer between Psk and Lt-TiO2:SnO2) was used to extract/transport electrons facilely, to form a bilayered ETL with a cascade CB, and to create a hydrophilic surface to deposit high-quality Psk films to enhance the photovoltaic performance of the PSCs. This study provides a blueprint for designing good-performance ETLs for high-efficiency, stable regular planar PSCs using various sized nanoparticles prepared in a very simple and low-cost way.

A selective and sensitive turn-on chemosensor for detection of Fe3+ in aqueous solution and its cell imaging in dorsal root ganglia neurons and MKN-45 cells.

A new turn-on fluorescent chemosensor (RBTM) for Fe3+ was designed based on Rhodamine B and a thiocarbonylimidazole moiety. The spectroscopic probe used for characterization of the synthesized system showed 300-fold fluorescence enhancement for the detection of Fe3+ with a 1:1 stoichiometry in EtOH/H2O solution (2:1, v/v, HEPES buffer, 1 mM, pH 7.30). Upon addition of Fe3+ in aqueous ethanol, the probe displayed a significant fluorescence enhancement and a distinct color change (colorless to pink) that can be detected by the naked eye. The binding constant between the probe and Fe3+ was determined to be 1.16 × 104 M-1 and the corresponding detection limit was calculated to be 0.256 µM. In addition, the energy gaps between the HOMO and LUMO in RBTM and RBTM-Fe3+ were calculated using DFT calculations to be 92.93 kcal/mol and 37.49 kcal/mol, respectively. The results indicate that binding of Fe3+ to RBTM lowered the HOMO-LUMO energy gap of the complex and stabilized the system. Fluorescence imaging experiments demonstrated that RBTM can be used as a fluorescent probe to detect Fe3+ in MKN-45 cells and dorsal root ganglia, thus revealing that RBTM could be used for biological applications.

Dual-binding pyridine and rhodamine B conjugate derivatives as fluorescent chemosensors for ferric ions in aqueous media and living cells.

Two new pyridine-type rhodamine B chemosensors (RBPO and RBPF) used to detect Fe3+ have been designed and synthesized, and the sensing behavior towards various metal ions was evaluated via UV-vis and fluorescence spectroscopic techniques. Both RBPO and RBPF not only have good spectral responses to Fe3+ in an EtOH/H2O solution (3 : 1, v/v, HEPES, 0.5 mM, pH = 7.33) with low detection limits and high binding constants, but also suffer from less interference from common metal cations. The two chemosensors are further proven to be practical in sensitively monitoring trace Fe3+ in real water specimens. Intracellular imaging applications demonstrated that RBPO and RBPF can be used as two fluorescent chemosensors for the detection of Fe3+ in living human breast adenocarcinoma (MCF-7) cells.

[Expression and clinical significance of Sema4C in esophageal cancer, gastric cancer and rectal cancer].

OBJECTIVE: To explore the expression and clinical significance of signal protein Sema4C in esophageal cancer, gastric cancer and rectal cancer. METHODS: Fifty esophageal cancer, 75 gastric cancer, 50 rectal cancer and 20 corresponding normal mucous membrane specimens, collected during the period of January 2008 to December 2010, were detected with streptavidin-peroxidase immunohistochemistry to detect the expression levels of Sema4C. And the relationships of the Sema4C expression with clinicopathological data was analyzed. RESULTS: The expression levels of Sema4C in three kinds of cancers were significantly higher than the corresponding normal mucous membranes (80.0% (n = 40) vs 20.0% (n = 4), 77.3% (n = 58) vs 25.0% (n = 5), 80.0% (n = 40) vs 15.0% (n = 3), all P = 0.000). Furthermore, the percentage of Sema4C positive cells was significantly higher in carcinoma nests of tumors with lymphatic metastasis than those without (90.3% (n = 28) vs 63.2% (n = 12), 85.0% (n = 51) vs 46.7% (n = 7), 92.0% (n = 23) vs 68.0% (n = 17), P = 0.049, 0.005, 0.034). However, no significant correlations were found between the Sema4C expression with gender, age, location of tumors, types of cancer cells, cell differentiation, tumor size, depth of invasion or tumor stage (all P > 0.05). CONCLUSION: There is a high expression of Sema4C in esophageal cancer, gastric cancer and rectal cancer. And it is strongly correlated with lymphatic metastasis. Thus Sema4C may play critical roles in the invasion and lymphatic metastasis of esophageal cancer, gastric cancer and rectal cancer.

Analysis of acinic cell carcinoma of the parotid gland - 15 years experience.

CONCLUSION: In our experience, the prognosis for parotid gland acinic cell carcinoma (AciCC) is good. Surgery alone would be sufficient in early-stage tumor. Postoperative adjuvant treatment in advanced-stage patients or those with positive resection margins usually gives satisfactory control of the disease. OBJECTIVES: AciCC is a rare tumor in parotid gland malignancy. The aim of this study was to retrospectively analyze the experience in our hospital in treating this malignancy. METHODS: Twenty-five patients with AciCC diagnosed from 1983 to 2007 at the Chang Gung Memorial Hospital were retrospectively reviewed. RESULTS: Thirteen male and 12 female patients ranged in age from 16 to 84 years (mean 37.5 years) at the time of diagnosis. Most patients (92%) presented with symptoms of infra-auricular mass. The tumor stage distributions of the patients were 24%, 44%, 28%, and 4% for stages I, II, III, and IV, respectively. Thirteen patients underwent superficial parotidectomy and 12 patients underwent total parotidectomy. Four patients had positive resection margins. Ten patients had surgery and postoperative radiotherapy; one received surgery and postoperative chemo/radiotherapy. The 10-year disease-free and overall actuarial survivals were both 84% in a mean follow-up of 75.8 months.

Primary mucosal melanoma of the nasal cavity and paranasal sinuses: 12 years of experience.

INTRODUCTION: Melanomas that arise in the nasal cavity or paranasal sinuses are rare and have a poor prognosis. In this study, we reviewed 15 patients in a tertiary referral centre and analyzed their treatment results and patterns of treatment failure. MATERIALS AND METHODS: Fifteen patients diagnosed from January 1994 to February 2005 at the Chang Gung Memorial Hospital were retrospectively reviewed. RESULTS: Eight men (53.3%) and seven (46.7%) women ranged in age from 51 to 85 years (mean 69.0 years) at the time of diagnosis. All patients presented with symptoms related to the nose. The majority of patients presented with epistaxis (93.3%). Ten patients received surgery and postoperative radiotherapy, three patients received surgery and postoperative chemo- and radiotherapy, and one patient received radiotherapy alone. The overall actuarial survival revealed that 49.5% were alive at 2 years and 33.0% were alive at 5 years. The average time from surgery to local recurrence was 5 months, the average time from surgery to the occurrence of regional recurrence was 7.45 months, and the time from surgery to the diagnosis of distant metastasis was 10.3 months. The sites of distant metastasis according to frequency are the lung, liver, bone, and brain. The average survival after the diagnosis of distant metastasis was 8 months. CONCLUSION: The prognosis of mucosal melanoma of the nasal cavity is poor in our experience. Most of the local recurrence, regional recurrence, and distant metastasis occurs in the first year after surgery. For those patients in the first year after surgery, frequent and regular follow-up is mandatory.

Synthesis and characterization of the air-water interfacial TiO2/ZrO2 binary oxide film.

TiO(2)/ZrO(2) binary oxide film was self-assembled using anionic surfactant (sodium dodecyl sulfonate (SDS)) as template and obtained at the air-water interface. X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were used to characterize the obtained film. The film was composed of many lamellar nanorods with a d spacing of 3.2 nm, and the lamellas were perpendicular to the lengthwise position of the rods. The energy-dispersive spectrum (EDS) was used for determining the titanium/zirconium atomic ratio. After being calcined, the sample decomposed to a mixture of anatase titania and tetragonal zirconia, and all the lamellar structure was broken.

Self-assembled nanodisks with targetlike multirings aggregated at the air-water interface.

In this communication, we report the self-assembly of zirconia by mixing its precursor with another solution containing surfactant as well as gelatin. The resulting zirconia product consists of many disks with a range of diameter from approximately 100 nm to approximately 2 mum. These disks can be assembled inside aqueous systems. Meanwhile the disks rise gradually and eventually form a visible film at the air-water interface. Remarkably, the structure of zirconia disks templated by surfactant has been found to be targetlike multirings with a d spacing of approximately 3.3 nm. We propose that a successful multirings self-assembly depends on two different template-functions from the same surfactant, excellent tenacity of the zirconia layers and the strong ability of the gelatin to stabilize and disperse the disks.