Carbazole‐based colorimetric and fluorescent probe for Cu2+ and its utility in bio‐imaging and real water samples

A new carbazole functionalized Schiff base CBM was synthesized and characterized. CBM can selectively recognize Cu²⁺ via UV–vis and fluorescence signal among common biologically relevant metal ions. When Cu²⁺ was added to CBM, there was a significant enhancement at the maximum absorption wavelength of 393 nm and with a distinct blue shift. The maximum emission peak was significantly attenuated by a factor of about 15 times at 535 nm and the blue shift of emission wavelength was observed. When other metal ions were added, there was no remarkable change at the maximum absorption and emission peak. Under the illumination of 365 nm ultraviolet lamp, the color of the CBM solution changed from light blue to dark blue after the addition of Cu²⁺. The combination mechanism of CBM with Cu²⁺ was nicely explored by density functional theory studies. The probe CBM has good cell permeability, fluorescence electron microscopy experiments show that CBM can be used as a fluorescent probe to detect the presence or absence of Cu²⁺ in Hela cells. Furthermore, the probe CBM can also be used for the detection of copper ions in actual water samples.     

A novel lipid droplets-targeting fluorescent probe based on dicyanisophorone and carbazole for Cu2+ and its application

A novel fluorescent probe, LCH , based on dicyanisophorone and carbazole, was prepared for the visual detection of Cu²⁺. The probe LCH could recognize Cu²⁺ by fluorescence quenching in EtOH/H₂O (1/4, v/v) solution, which could be easily identified under the 365 nm UV lamp, and the detection limit was as low as 0.785 μM. The recognition mechanism of probe LCH with Cu²⁺ was determined by combining ¹H NMR titration, MS, and theoretical calculations. Practical application experiments showed that probe LCH could be used to detect Cu²⁺ in the test strip experiments. Cell imaging experiments showed that the probe LCH owned good cell permeability and could be applied to the imaging of Cu²⁺ in HepG2 cells. In addition, fluorescence colocalization experiments showed that LCH could target lipid droplets. These results indicate that the probe LCH will have a good application prospect in environmental detection and clinical medicine.     

A highly sensitive naphthalimide-based fluorescent probe for detection of Cu2+ via selective hydrolysis reaction and its application in practical samples

A novel fluorescent probe CN3, containing 1,8-naphthalimide and picolinate units, was synthesized, and its structure was characterized by ¹H nuclear magnetic resonance spectroscopy (H NMR), ¹³C nuclear magnetic resonance spectroscopy (C NMR), and mass spectroscopy techniques. The detection property of CN3 toward copper ions (Cu²⁺) has been investigated in ethanol–HEPES buffer (v/v = 1/1, pH = 7.40) solution by UV–Vis absorption and fluorescence emission spectra. The results showed that CN3 had a highly selective and sensitive fluorescence quenching response to Cu²⁺, which was attributed to the generation of weak fluorescent N-ethyl-4-hydroxyphenyl-1,8- naphthalimide (compound 2) in polar ethanol–HEPES buffer (v/v = 1/1, pH = 7.40) via selective hydrolysis reaction. The detection of CN3 for Cu²⁺ was not influenced in the presence of other competing metal ions, and the limit of detection was as low as 50.0 nM. Therefore, the color of CN3 changed from colorless to yellowish when the Cu²⁺ was added. Furthermore, the fluorescent probe CN3 was utilized to detect Cu²⁺ in real water samples with fine performance.     

A dual-function chemosensor based on coumarin for fluorescent turn-on recognition of Hg2+ and colorimetric detection of Cu2+ in aqueous media

A novel coumarin derivative CTT was synthesized via the condensation of 7-(N,N-diethylamino) coumarin-3-aldehyde with 5-amino-1,3,4-thiadiazole-2-thiol and its structure was characterized using infrared spectroscopy (IR), ¹H NMR, mass spectrometry (MS) techniques, and elemental analysis. The recognition properties of CTT with metal ions were investigated in CH₃CN–H₂O (v/v = 1/1) solution using UV–vis absorption and fluorescence emission spectrum method. The results showed that CTT could monitor Cu²⁺ and Hg²⁺ simultaneously as a dual-function chemosensor in CH₃CN–H₂O (v/v = 1/1). CTT could be used to detect Cu²⁺ colorimetrically; when using CTT, a color change from yellowish-brown to yellowish-green could be readily observed by the naked eye. CTT showed turn-on fluorescent recognition of Hg²⁺, the fluorescence enhancement was attributed to the inhibited C=N isomerization and the obstructed excited state intramolecular proton transfer (ESIPT) of CTT. The recognition mechanism of CTT for Cu²⁺ and Hg²⁺ was studied by experiments and theoretical calculations, respectively. Therefore, CTT has the ability to be a “single chemosensor for dual targets.”     

Preparation and nonlinear optical properties of two acrylate polymers bearing different long conjugated pendants

Two new acrylate monomers containing different long π-election conjugation bridge structure, 4′-[(N,N-diethylacrylate) amino], 4-(pyridine-4-vinyl) stilbene (DAS) and 4′-[(N,N-diethylacrylate) amino], 4-(pyridine-4-vinyl) azobenzene (DAA), were synthesized and their copolymers with methyl methacrylate (MMA) were prepared by free radical polymerization method. Their structures and properties of these copolymers were characterized and evaluated by FTIR, ¹H-NMR, UV spectra, GPC and Z-scan technique with 8 ns pulses at 532 nm wavelength. The relationship between their structures and properties was investigated. The results show that the structure of these resultant copolymers can be effectively tuned by simply varying the feed ratio and these copolymers exhibit good solubility and large third-order nonlinear optical properties. The large third-order nonlinear optical properties are mainly attributed to the substituted NLO-chromophore with long D-π-A conjugated structure. Simultaneously, it is found that poly (DAA-co-MMA) with N=N double bond as conjugation bridge has larger third-order nonlinear optical susceptibility than poly (DAS-co-MMA) with C=C double bond as conjugation bridge owing to more effective π electron conjugation effect.     

氧化铜/二氧化硅多孔复合材料的制备及其对亚甲基蓝的吸附性能

采用聚乙二醇（PEG）为模板,通过溶胶凝胶法-水热法制备出CuO/SiO2多孔复合材料,使用FTIR、HRTEM、XRD和BET等技术手段对目标产物进行了表征;研究添加CuO质量及反应温度等反应条件对复合材料的孔结构特征的影响。 用目标产物作为吸附材料,研究了其对有机染料亚甲基蓝的吸附性能,结果表明,CuO/SiO2多孔复合材料对亚甲基蓝具有良好的吸附效果,尤其是含CuO质量分数为15%的样品在用量0.015 g、体系pH=9、搅拌时间为2 h的条件下,对10 mL亚甲基蓝（4 mg/L）的去除率最高可达97.17％。 对吸附的过程和机理进行了初步探讨。     

"三明治夹心"型Ni-P@Ni-B/Ni电极的制备及高效全pH下的催化制氢性能

通过化学镀法制备了具有“三明治夹心”结构的Ni-P@Ni-B/Ni催化电极. 该催化材料为直径1 μm左右的微球. 电化学性能测试结果表明, 在电流密度为10 mA/cm ²时, 其在0.5 mol/L PBS缓冲液(pH=7)中的过电位仅为287 mV, 在此电位下连续工作24 h后, 电流密度仅衰减了7.6%. 同时Ni-P@Ni-B/Ni在酸性(0.5 mol/L H₂SO₄)和碱性(1 mol/L KOH)条件下也具有优异的析氢反应催化活性, 达到相同电流密度时过电位分别为199和79 mV. 该工作为全pH环境下高效电解水制氢提供了新思路.     

1—（5—溴—2—吡啶偶氮）—2—萘酚—6—磺酸与铁（Ⅱ）显色反应的研究及其应用

本研究了１－（５－溴－２－吡啶偶氮）－２－萘酚－６－磺酸（５－Ｂｒ－ＰＡＮ－Ｓ）与铁（Ⅱ）的显色反应，试验表明，在ｐＨ３－１０范围内铁（Ⅱ）与５－Ｂｒ－ＰＡＮ－Ｓ型成稳定的络合物，络合物在５５０ｎｍ和７５０ｎｍ有二个吸收峰，其表现摩尔吸光系数分别为２．３１×１０＾４和１．７７×１０＾４Ｌ．ｍｏｌ＾－＾１．ｃｍ＾－＾１。络合物组成比为铁（Ⅱ）：５－Ｂｒ－ＰＡＮ－Ｓ＝１：２，络合物稳定常数为１．８２     

缺氧响应荧光探针的成像及治疗应用

由于肿瘤内部细胞远离血管, 其氧气消耗量远远超出血液供应量, 因此容易导致肿瘤缺氧. 肿瘤缺氧会引发肿瘤扩散加速、 诱导某些基因过表达及产生药物抗药性等问题. 基于此, 发展性能优异的缺氧响应荧光探针对肿瘤的诊断和治疗具有重要意义. 本文对缺氧响应荧光探针在成像及治疗方面的应用进展进行了综合评述, 介绍了硝基、 偶氮键和醌3种常用的缺氧响应基团, 并探讨了它们在缺氧微环境下的识别机理; 介绍了缺氧响应荧光探针的构建及其在生物成像方面的最新研究成果; 总结了缺氧响应荧光探针在基因治疗、 光动力学治疗、 化学治疗及协同治疗方面的研究进展; 展望了缺氧响应荧光探针在临床诊断和治疗方面的应用前景.