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The probe CT was synthesized and investigated as a novel label-free chemosensor for Ga 3 + detection in water. Probe CT showed remarkable selectivity and sensitivity for Ga 3 + in Tris–HCl aqueous buffer solution (pH 7.0). The chemosensor responded rapidly to Ga 3 + with a 1:1 stoichiometry. Meanwhile, the unapparent changes of fluorescence lifetime decays suggest the turn-on process of probe CT by Ga 3 + which appears to be a static mechanism. [ABSTRACT FROM AUTHOR]

Due to its high toxicity, long durability, easy absorption by aquatic organisms, and significant bioaccumulation, Hg2+ has caused substantial environmental damage and posed serious threats to human health. Therefore, effective detection of Hg2+ is of utmost importance. In this study, a turn-on fluorescent probe based on dicyanoisoflurone was developed for the detection of Hg2+. The probe exhibited near-infrared fluorescence signal at 660 nm upon excitation by 440 nm UV light in a mixture of CH3CN and HEPES buffer (4:1, v/v, 10 mM, pH = 7.5), with selective binding to Hg2+ in a molar ratio of 1:1. This binding event was accompanied by a visible color change from light yellow to orange. By utilizing the enhanced fluorescence signal change, this probe enables highly sensitive analysis and detection of Hg2+ with excellent selectivity (association constant = 1.63 × 104 M− 1), large Stokes shift (220 nm), high sensitivity (detection limit as low as 5.6 nM), short reaction time (30 s), and a physiological pH range of 7.5–9.5. The probe was successfully employed for detecting of Hg2+ in real water and living cells. [ABSTRACT FROM AUTHOR]

Zinc(II) ions (Zn2g) play crucial roles in the growth, propagation, and metabolism of animals, plants, and humans. Abnormal concentrations of Zn2+ in the environment and living organisms pose potential risks to environmental protection and human health. Therefore, it is imperative to develop rapid, reliable and in-situ detection methods for Zn2+ in both environmental and biological contexts. Furthermore, effective analytical methods are required for diagnosing diseases and understanding physiological metabolic mechanisms associated with Zn2+ concentration levels. Organic small-molecule fluorescent probes offer advantages such as fast, reliable, convenient, non-destructive detection capabilities and have significant application potential in Zn2+ detection and bioimaging; thus garnering extensive attention. Over the past two years alone, various organic small-molecule probes for Zn2+ based on different detection mechanisms and fluorophores have been rapidly developed. However, these probes still exhibit several limitations that need further resolution. In light of this context, we provide a comprehensive summary of the detection mechanisms, performance characteristics, and application scope of Zn2+ fluorescence probes since year 2022 while highlighting their advantages. We also propose solutions to address existing issues with these probes and outline future directions for their advancement. This review aims to serve as a valuable reference source offering insights into the development of advanced organic small-molecule-based fluorescence probes specifically designed for detecting Zn2+. [ABSTRACT FROM AUTHOR]

The detection and removal of Pb2+ is of utmost importance for environmental protection and human health due to its toxicity, persistent pollution, and bioaccumulation effects. To address the limitations associated with organic small molecule-based fluorescence probes such as poor water solubility and single functionality in detecting Pb2+, a fluorescence probe based on halloysite nanotubes was developed. This probe not only enables specific, rapid, and reliable detection of Pb2+ but also facilitates efficient removal of it from water. The development of this bifunctional fluorescent probe provides a valuable insight for designing more advanced probes targeting heavy metal ions. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to explain the associations between different types of uveitis and human leukocyte antigen (HLA)-B27, HLA-DR4, and HLA-DRw53., Methods: A retrospective analysis of 390 uveitis cases was conducted among inpatients and outpatients diagnosed at Weifang Eye Hospital from 2013 to 2016. All 390 patients underwent HLA-B27 examination, and an additional 40 patients underwent examination for HLA-DR4 and HLA-DRw53. Gender, age, corrected visual acuity (CVA), and recurrence frequency were statistically analyzed based on the onset site and etiology classification., Results: Among the 390 enrolled patients, 206 were male, and 183 were female, with ages ranging from 6 to 87 years (mean: 44.2). The disease onset was classified into anterior uveitis (AU), panuveitis (panU), posterior uveitis (PU), and intermediate uveitis in 180, 112, 88, and 10 cases, respectively. HLA-B27 was positive in 94 cases (53 males and 41 females), yielding a positive rate of 24.1%. In AU patients, 80 (44.4%) tested positive for HLA-B27, while 8 (7.1%) panU patients and 6 PU patients (6.8%) were HLA-B27 positive; none of the intermediate uveitis (IU) patients exhibited HLA-B27 positivity. HLA-B27, HLA-DR4, and HLA-DRw53 examinations were performed on 40 patients with binocular uveitis, resulting in 2 HLA-B27 positive cases, 15 HLA-DR4 positive cases, and 20 HLA-DRw53 positive cases, with positive rates of 5%, 37.5%, and 50%, respectively. Among 25 Vogt Koyanagi-Harada (VKH) cases, 1 tested positive for HLA-B27, 22 were positive for HLA-DR4, and 24 were positive for HLA-DRw53, with positive rates of 4%, 88%, and 96%, respectively. No positive HLA-B27, HLA-DR4, or HLA-DRw53 cases were found among the 10 cases of Behcet's disease (BD)., Conclusions: Human leukocyte antigens (HLAs) play a significant role in the mechanism of uveitis. HLA-B27 exhibits high diagnostic value in acute AU, while HLA-DR4 and HLA-DRw53 are crucial for diagnosing binocular uveitis, particularly Vogt Koyanagi-Harada (VKH) syndrome. Further investigation is warranted to explore the relationship between HLA-DR4, HLA-DRw53, and uveitis.

Zinc (Zn 2+ ) and lead (Pb 2+ ) ions in the environment have important effects on human health and environmental safety. Therefore, it is necessary to effectively detect them by a convenient and reliable analysis method. In this study, two near-infrared fluorescent probes for the fast determination of Zn 2+ and Pb 2+ were synthesized by a simple Schiff base reaction between the dicyanoisophorone skeleton and carbohydrazide derivatives. Among them, the probe with the thiophene-2-carbohydrazide group showed a selective fluorescence response to Zn 2+ and Pb 2+ with a maximum emission wavelength of 670 nm. And the detection limits of the probe for Zn 2+ and Pb 2+ were 1.59 nM and 1.65 nM, respectively. In contrast the probe modified by the furan-2-carbohydrazide group achieved quantitative detection of Zn 2+ , with a detection limit of 2.7 nM. These results were attributed to the fact that the probes bind to Zn 2+ and Pb 2+ in stoichiometric ratios of 1:1, blocking the intramolecular PET effect. Furthermore, these two probes can be recycled through the action of EDTA and have been successfully used to detect Zn 2+ and Pb 2+ in real water samples., (© 2022 IOP Publishing Ltd.)

ABSTACTWith the widespread use of N 2 H 4 , it brings potential risk to human health and environmental safety because of its diverse toxicological functions. In order to determine N 2 H 4 effectively in both environment and living systems, all kinds of fluorescence probes have been prepared for the specific response of N 2 H 4 based on various mechanisms and different acceptor group for N 2 H 4 . This paper provides a review to bring more inspirations for the development of the fluorescent probes for N 2 H 4 .

Iron and titanium doped γ-Al 2 O 3 (γ-Fe-Ti-Al 2 O 3 ) mesoporous catalysts were synthesized by evaporation-induced self-assembly using glucose as template, and applied to ozonation of ibuprofen in bromide-containing water. X-ray diffraction (XRD), nitrogen adsorption-desorption (BET), X-ray photoelectron spectroscopy (XPS) results showed that iron and titanium successfully doped into the skeleton of γ-Al 2 O 3 , uniform distribution, maintain the ordered mesoporous structure of γ-Al 2 O 3 , with larger specific surface area. The valence of titanium coexists with Ti 4+ and Ti 3+ , and the valence of iron was Fe 3+ . Infrared spectra of chemisorbed pyridine (Py-FTIR) results showed that the doped titanium and iron into the framework position of γ-Al 2 O 3 altered the surface acidity of the alumina surface, especially increasing the medium Lewis acid sites, which was conducive to the effective decomposition of ozone into active oxygen species. The γ-Fe-Ti-Al 2 O 3 catalyst (Al/Fe = 25, Al/Ti = 75) enhanced the removal rate of ibuprofen in ozonation of bromide-containing water, and effectively blocked the formation of bromate. After the reaction of 60 min, the removal rate of TOC was increased from 54% of γ-Al 2 O 3 /O 3 to 86% with γ-Fe-Ti-Al 2 O 3 /O 3 , while the ozonation alone was only 13%. Electron Paramagnetic Resonance (EPR) spectra showed that hydroxyl and superoxide radicals were reactive oxygen species, which was beneficial to the mineralization of organic matter. The capture experiment of Fe 2+ ion confirmed that the electronic cycle of Fe 2+ ion and Fe 3+ ion was beneficial to block the formation of bromated. The addition of ibuprofen and humic acid can enhance the reduction of Fe 3+ in the catalytic ozonation of γ-Fe-Ti-Al 2 O 3 , which further strengthened the blocking of bromate formation.

Hydrosulphite (HSO 3 - ), as a common and important chemical reagent, is widely used in everyday life, however excessive use and abuse of HSO 3 - can cause potential harmful effects on the environment and in biological health. In this paper, we describe the design and preparation of a colorimetric and ratiometric fluorescence probe for the visual detection of HSO 3 - (excitation wavelengths were, respectively, 336 nm and 520 nm). This method showed some advantages including simple preparation, high selectivity, fast response, and significant colour and fluorescence ratio (F 450 /F 594 ) changes in the presence of HSO 3 - . In addition, this probe was used successfully for the detection of HSO 3 - in real water samples and showed a good recovery rate range., (© 2021 John Wiley & Sons, Ltd.)

A Schiff's base derivative was synthesized using a condensation reaction between 8-formyl-7-hydroxy-4-methylcoumarin and furan-2-carbohydrazide that produced marked aggregation-induced emission and had excellent ability to specifically recognize aluminium ions (Al 3+ ). This compound displayed faint fluorescence in the benign solvent dimethyl formamide, and exhibited obvious green fluorescence following addition of specific amounts of water. Moreover, it exhibited strong blue fluorescence after combination with Al 3+ even in the presence of other interfering ions. These experimental results demonstrated that this derivative could be used as a fluorescence probe for Al 3+ . The advantages, including significant fluorescence change, high selectivity and sensitivity, and fast response, meant that this probe could be used both to detect Al 3+ in water samples and for fluorescence imaging in living cells., (© 2019 John Wiley & Sons, Ltd.)