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171.
A novel fluorescent tweezer was designed and synthesised to sense hydrophobic amines in aqueous solution. Association of the guest was driven by both hydrophobic effect and electrostatic interactions, with the hydrophobic interactions being dominant. The affinity and selectivity of the sensor for amine-based stimulants are reported. 相似文献
172.
Vincent Martinez Prof. Dr. Maged Henary 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(39):13764-13782
Nile red and Nile blue are highly fluorescent and photostable organic dyes from the benzo[a]phenoxazine family. They have been used as histological stains for imaging lysosomes and lipids in vitro. The dyes’ high quantum yields and solvent‐dependent optical properties make them ideal scaffolds for the development of pH probes and local polarity indicators. Reviews of the literature in this area are scarce with only one review ever published in 2006. It has been 10 years since and the field has evolved. This review aims to expand upon topics covered by the previous reviewers and to report on recent advances in the literature. As authors, we hope to convey a sense of scope and to spark renewed interest in this useful niche of dye chemistry. 相似文献
173.
《Journal of polymer science. Part A, Polymer chemistry》2018,56(11):1155-1161
A new turn on fluorescent probe for ferric ion based on poly(m‐phenyleneethynylene salicylaldimine) ( PPE‐IM ) has been developed. The preparation of PPE‐IM involves post‐polymerization functionalization of the corresponding polymeric amine, PPE‐AM , via the condensation with salicylaldehyde. The degree of polymerization of both PPE‐IM and PPE‐IM is 17 with polydispersity index of 1.5. In aqueous solution, the polymeric PPE‐IM is highly stable unlike its small molecule analog which is gradually hydrolyzed. The weak fluorescence of initial PPE ‐ IM (λem = 470) is greatly enhanced by 300 folds upon the addition of Fe3+. The 1H NMR reveals that the fluorescence enhancement is caused by Fe3+‐induced hydrolysis of the imine group. The sensing system shows a detection limit of 0.14 μM of Fe3+. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 1155–1161 相似文献
174.
《化学:亚洲杂志》2017,12(16):2033-2037
The immunochromatographic assay (ICA) using a nitrocellulose (NC) membrane offers several advantages. This technique is a rapid and straightforward method in contrast to other immunoassays. Polydiacetylene (PDA) vesicles have unique optical properties, displaying red color and red fluorescence at the same time. In this system, red‐phase PDA vesicles are used as a fluorescent dye as well as a surface for immobilized hepatitis B surface antibody (HBsAb). PDA has a remarkable stability compared with other fluorescent dyes. In this study, the most suitable PDA/HBsAb complexes are introduced for detecting hepatitis B surface antigen (HBsAg). Then, the PDA/HBsAb complexes affixed antibody is attached to NC membrane, which has two lines to confirm detection of HBsAg. The main advantage of this system is that the detection of HBsAg can be observed in both visible and fluorescent images due to the optical properties of polydiacetylene. Detection of HBsAg is observed up to 0.1 ng mL−1 by fluorescent analysis and confirmed by red line on the NC membrane up to 1 ng mL−1 (HBsAg) using the naked eye. Consequently, these results show that PDA/HBsAb complexes were successfully applied to ICA for the diagnosis of hepatitis B. 相似文献
175.
176.
Dr. Anaïs Depaix Agnieszka Mlynarska-Cieslak Dr. Marcin Warminski Dr. Pawel J. Sikorski Prof. Dr. Jacek Jemielity Dr. Joanna Kowalska 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(47):12190-12197
Labeled RNAs are invaluable probes for investigation of RNA function and localization. However, mRNA labeling remains challenging. Here, we developed an improved method for 3′-end labeling of in vitro transcribed RNAs. We synthesized novel adenosine 3′,5′-bisphosphate analogues modified at the N6 or C2 position of adenosine with an azide-containing linker, fluorescent label, or biotin and assessed these constructs as substrates for RNA labeling directly by T4 ligase or via postenzymatic strain-promoted alkyne-azide cycloaddition (SPAAC). All analogues were substrates for T4 RNA ligase. Analogues containing bulky fluorescent labels or biotin showed better overall labeling yields than postenzymatic SPAAC. We successfully labeled uncapped RNAs, NAD-capped RNAs, and 5′-fluorescently labeled m7Gp3Am-capped mRNAs. The obtained highly homogenous dually labeled mRNA was translationally active and enabled fluorescence-based monitoring of decapping. This method will facilitate the use of various functionalized mRNA-based probes. 相似文献
177.
ABSTRACTHerein, we develop a switchable peptide-equipped protein/cucurbit[7]uril (CB[7]) supramolecular assembly as novel targeted drug vector. Specifically, bovine serum albumin (BSA) is used to interact with CB[7], serving as the core of drug vector. Then, a peptide shield layer is formed on the surface of BSA/CB[7], yielding peptide-equipped supramolecular assembly (Pep@BSA@CB[7]). The equipped peptide shield layer is composed of switchable peptide probes consisting of a polycationic cell-penetrating peptide (CPP) motif, a polyanionic motif and a linking motif, and therefore provides a variety of desirable properties. First, the CPP motif displays excellent cell penetration ability and can facilitate internalisation of the drug vector. Secondly, the polyanionic motif performs intramolecular electrostatic interaction with CPP motif and thereby can reduce non-targeted delivery towards normal cells. Thirdly, the linking motif can be specifically cleaved by matrix metalloproteinases 2 that is up-regulated in tumour microenvironment, thus enabling precise cancer-targeting. As a consequent, Pep@BSA@CB[7] can serve as a promising drug vector that exhibits superior targeting ability and high uptake efficiency towards cancer cells, which may be of great potential in cancer-targeted treatment. 相似文献
178.
Zhijie Fang Zhe Su Wenjing Qin Hao Li Bing Fang Wei Du Qiong Wu Bo Peng Peng Li Haidong Yu Lin Li Wei Huang 《中国化学快报》2021,31(11):2903-2908
H2S is an essential gas signal molecule in cells, and viscosity is a key internal environmental parameter. Recent studies have shown that H2S acts as a cytoarchitecture agent and gas transmitter in many tissues, e.g., as a regulator of neuroendocrine in the brain for mediating vascular tone in blood vessels. Mitochondrial viscosity is an important parameter for judging whether mitochondrial function is normal. It has been reported that oxidative stress and mitochondrial dysfunction are connected with Parkinson’s disease (PD), and the protective role of H2S in PD models has been extensively demonstrated. Herein, Mito-HS, a new two-photon fluorescent probe was demonstrated to detect cross-talk between the two channels of mitochondrial viscosity and H2S content. Moreover, this probe could detect the relative amount of and changes in mitochondrial H2S in situ due to the reduced mitochondrial targeting ability after reaction with H2S. The results show that H2S in mitochondria is inversely related to viscosity. The PD model has a lower H2S in mitochondria and a higher mitochondrial viscosity than did the normal. This result is important for our deep understanding of PD and its causes. 相似文献
179.
《Journal of Coordination Chemistry》2012,65(3):417-426
Abstract The electrochemical behavior of VOQ2OH or [VOQ2-OVOQ2] (Q = 8-hydroxyquinohnate anion) has been investigated by cyclic voltammetry in acetonitnie solutions. Although both species exist simultaneously at every condition analyzed, they can be clearly differentiated by this method. The effect of trace amounts of water on the electrochemical behavior is also discussed. 相似文献
180.
Andrea Liscio Massimo Bonini Emanuele Treossi Emanuele Orgiu Marcel Kastler Florian Dötz Vincenzo Palermo Paolo Samorì 《Journal of Polymer Science.Polymer Physics》2012,50(9):642-649
A prototypical semiconducting bicomponent system consisting of a conjugated polymer, that is, poly(3‐hexylthiophene) (P3HT), blended with a small thiophene containing conjugated molecule, that is, an alkyl‐substituted bisphenyl‐bithiophene [phenylene–thiophene–thiophene–phenylene (PTTP)], has been used as an electroactive active layer in field‐effect transistors (FETs). The self‐assembly of this bicomponent system at surfaces has been studied at different length scales, from the nanoscale to the macroscale, and compared with the behavior of monocomponent films of PTTP and P3HT. The correlation between morphology and electric properties of the semiconducting material is explored by fabricating prototypes of FETs varying the relative concentrations of the two‐component blend. The maximum charge carrier mobility value, achieved with a few percent of PTTP component, is not simply due to a uniform dispersion of the molecules in the polymer matrix, but rather to the generation of very long percolation paths, whose composition and electrical properties can be tuned with the PTTP concentration. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012 相似文献