Fluorescent Probe ABM for Screening Gastrointestinal Patient’s Immune State

The fluorescent probe-aminoderivative of benzanthrone, ABM (developed at Riga Technical University, Riga, Latvia) was used to characterize the membranes of lymphocytes of cancer patients: 46 patients with gastrointestinal diseases, 13 patients having different primary localizations with massive metastases and intoxication. Patients were divided into three groups: (1) with decreased fluorescence intensity, (2) normal fluorescence intensity, (3) increased fluorescence intensity. The lymphocytes distribution among subsets differed between groups, in correspondence to the level of florescence intensity. Surgical treatment affected the main immunological parameters and elevated the functional activity of lymphocytes. In the advanced tumors group, fluorescence intensity correlates with the survival rate. Results suggest that determination of lymphocytes functional activity by ABM can aid evaluation of the immune status in cancer patients.     

A Fe<Superscript>3+</Superscript>/Hg<Superscript>2+</Superscript>-Selective Anthracene-Based Fluorescent PET Sensor with Tridentate Ionophore of Amide/β-Amino Alcohol

A new anthracene-based fluorescent PET sensor 1 with a tridentate ionophore of amide/β-amino alcohol displays very good selectivity and sensitivity for Fe³⁺ (K _a = 1.6 × 10³ M⁻¹) and Hg²⁺ (K _a = 2.1 × 10³ M⁻¹) in CH₃CN–H₂O (3:7, v/v) with detection limit of 1 μM. More fluorescence enhancement was observed when 1 selectively detected Fe³⁺ or Hg²⁺ in CH₃CN and its detection limit was up to 0.03 μM.     

Small luminescent molecular probe for developing as assay for alkaline phosphatase

Alkaline phosphatase (ALP) is an important biomarker in clinical diagnostics, and the abnormal level of ALP enzyme in serum is closely related to various diseases such as bone metastases, bone or liver cancer, and extrahepatic biliary obstruction. Recognizing the location and expression level of ALP in live cells has a substantial importance in early-stage cancer diagnosis, as well as an important parameter for studying the recovery of the patients after liver transplantation. With the advent of the newer and advanced fluorescence imaging techniques, small-molecule fluorescent probes have become a very powerful tool for mapping the subtle changes in the enzyme expression level in living cells and tissues in real-time. In this account, we provide an overview of recent advances in small-molecule ALP fluorescent probes, mainly during the last few years, including the design strategies and applications for biological applications.     

荧光探针在氰化物分析中的研究进展

氰化物极易与细胞色素氧化酶键合,抑制电子转移、导致组织缺氧,从而显示较强的毒性。荧光化学传感器作为简易、灵敏且可视化的方法广泛应用于氰化物的检测。本文对荧光探针在氰化物检测中的应用进行综述,概述了氰化物的毒性机制和荧光探针对氰化物的响应机理。同时,本文总结了荧光探针在水体、食品和生物组织中对氰化物的检测及生物成像中的应用,并对荧光探针在结构设计中如何提高生物兼容性和靶向性等进行了展望,以期为光化学探针分子的设计及应用提供理论与研究依据。     

Long-term super-resolution imaging of mitochondrial dynamics

Monitoring dynamics of mitochondria has become an essential approach to explore the function of mitochondria in living cells with the emergence of super-resolution fluorescence microscopy. However, long-term super-resolution imaging of mitochondria is still challenging due to the lack of photostable fluorescent probes and stable mitochondria-specific markers which are not affected by the changes of mitochondrial membrane potential. Here, we introduce a method for long-term imaging mitochondrial dynamic through the SNAP-tag fluorogenic probe based on 4-azetidinyl-naphthalimide derivatives. Using structured illumination microscopy (SIM), we observed the fusion and fission of mitochondria over a course of 16 min at 109 nm resolution. Furthermore, the interactions as well as fusion between mitochondria and lysosomes were studied during mitophagy at the nanoscale. Convincingly, the combination of SNAP-tag fluorogenic probes and super-resolution fluorescence microscopy will offer a new way to monitor dynamic mitochondria in living cells.     

A ratiometric near-infrared naphthalimide-based fluorescent probe with high sensitivity for detecting Fe2+ in vivo

Iron is one of the essential trace elements in the human body. It plays an important role in human biology and pathology. Deregulation of iron levels in cells is associated with disease development. In this work, we synthesized a novel near-infrared intramolecular charge transfer (ICT) based ratiometric fluorescent probe to detect Fe²⁺, by using naphthalimide and indole moieties as building blocks. Our work showed that the radiometric probe has excellent selectivity, sensitivity and rapid response. Moreover, we could successfully perform real-time monitoring of Fe²⁺ in HeLa cells and C. elegans.     

A fluorescent probe for Hg2+sensing in solutions and living cells with a wide working pH range简

In this paper, 2-carboxybenzaldehyde rhodamine B thiohydrazine(1) was synthesized and developed as a fluorescent probe to recognize Hg2+in DMF/H2 O(1:9, v/v) solution with high selectivity. The probe can be applied to the quanti?cation of Hg2+with a linear concentration range covering from 1.0×10-7mol/L to 1.0×10-5mol/L(R2= 0.9985) and a detection limit of 4.2×10-8mol/L. The experiment results show that the response of probe 1 to Hg2+is pH-independent in a wide range from 4.0 to 9.0. Moreover, the probe 1 exhibits excellent selectivity toward Hg2+over other common metal cations. Most importantly, the probe can be employed to monitor Hg2+in living cells using fluorescent imaging technique with satisfied results.     

Turn-on fluorescence sensing of cyanide ions in aqueous solution简

A sensitive fluorescent probe, 2,2＇-bisbenzimidazole （L）, for CN has been developed. This structurally simple receptor displays great selectivity for the cyanide anion over other common inorganic anions in an aqueous environment. In addition, further study demonstrates the lower detection of the fluorescence response of the sensor to CN is in 10 9 mol/L range. Thus, the present probe should be applicable as a practical system for the monitoring of cyanide concentrations in aqueous samples.     

Influence of Gd doping on the absolute quantum efficiency and lifetime of EuxGd1-x（TTA）3phens

Absolute quantum yield （Ф） is one of the most important parameters to evaluate the potential of novel materials. Lanthanide complexes EuxGd1-x（TTA）3phens are synthesized with the ratio of Gd3＋ dopant concentration ranging from 10% to 90% to improve the absolute quantum yield. EuxGd1-x（TTA）3phens possess similar infrared and ultraviolet spectra, showing that they have similar molecular structures. The absolute emission quantum yields of EuxGd1-x（TTA）3phens are determined using a fluoromax-4 spectrofluorometer equipped with an integrating sphere. The fluorescence lifetimes of the EuxGd1-x（TTA）3phens are measured in the same experiment. It was found that both absolute quantum yields and fluorescence lifetimes of EuxGd1-x（TTA）3phens are of quasi-periodic variation with the change of the Gd3. dopant concentrations. The absolute quantum efficiency and fluorescence lifetime vary with respect to the Gd content in an opposite fashion, indicating that the rate of energy absorption by the EuxGd1-x（TTA）3phens and the conversion to light energy is critical for the absolute quantum efficiency. The radiative rate constant Kr and non-radiative rate constant Knr are calculated. The dependence of Kr and Knr on the Gd3＋ dopant concentrations is very similar to that of absolute quantum efficiency. The radiation rate constant Kr and absolute quantum efficiency have a linear relationship.     

一种新型Cu2+离子荧光探针的合成及性能研究

以4-(二乙氨基)水杨醛为原料,经7-二氨基-3-羧酸香豆素合成了一种新型酰胺类Cu2+荧光探针1。本实验具有合成原料经济易得,合成方法简单易行的特点。并且该探针对Cu2+的检测具有良好的离子选择性,抗干扰性能和较高的检测灵敏度,探针1的浓度为10-5 mol/L时检测限达到2.4×10-7mol/L。同时该探针可以与Cu2+离子1：2的摩尔比络合。