Transition metals (d-blocks) are recognized as playing critical roles in biology, and they most often act as cofactors in diverse enzymes; however, improper regulation of transition metal stores is ...also connected to serious disorders. Therefore, the monitoring and imaging of transition metals are significant for biological research as well as clinical diagnosis. In this article, efforts have been made to review the chemical sensors that have been developed for the detection of the first-row d-block metals (except Cu and Zn): Cr, Mn, Fe, Co, and Ni. We focus on the development of fluorescent sensors (fall into three classes: "turn-off", "turn-on", and ratiometric), colorimetric sensors, and responsive MRI contrast agents for these transition metals (242 references). Future work will be likely to fill in the blanks: (1) sensors for Sc, Ti, and V; (2) MRI sensors for Cr, Mn, Co, Ni; (3) ratiometric fluorescent sensors for Cr(6+), Mn(2+), and Ni(2+), explore new ways of sensing Fe(3+) or Cr(3+) without the proton interference, as well as extend applications of MRI sensors to living systems.
The discriminatory detection of Cys/Hcy, GSH and H2S in living cells and organism (zebrafish) was realized by a triple-emission fluorescent probe TCAN through the combination of three distinct ...fluorescence signals (blue-green-red).
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•A triple-emission fluorescent probe, TCAN, was developed for the discriminatory detection of Cys/Hcy, GSH and H2S.•TCAN was successfully used for imaging Cys/Hcy, GSH and H2S in living cells and zebrafish.•TCAN is the first fluorescent probe to differentiate Cys/Hcy, GSH and H2S in living organisms (zebrafish) using three-color fluorescence imaging.
Biothiols such as Cys, Hcy, GSH, and H2S are a critical branch of reactive sulfur species (RSS) and play indispensable roles in human physiological processes. To better understand the intricate and symbiotic networks between these biothiols in physiological processes, single-molecule fluorescent probes to simultaneously distinguish them are highly desirable. Herein, we judiciously conjugated an azide-functionalized tetrahydroquinoxaline coumarin precursor with a NBD-masked 7-hydroxycoumarin through an ester bond to develop a robust fluorescent probe, TCAN, for the differentiation of Cys/Hcy, GSH, and H2S. TCAN displayed three distinct fluorescence signals in response to biothiols: blue-green for Cys/Hcy, blue for GSH, and blue-red for H2S. Significantly, the first discriminatory detection of Cys/Hcy, GSH and H2S in living organisms (zebrafish) was realized using probe TCAN.
Benzoyl peroxide (BPO) has been added in wheat flour because of its bleaching effect. However, the abnormal used BPO has caused increasing concern due to its strong oxidization capability which may ...have adverse effects on living organisms. Herein, we present a carbon dot (CD)-based fluorescent and colorimetric probe for visually, sensitively and selectively sensing BPO. The addition of BPO could quench the red fluorescence of CDs peaked at 622 and 677 nm, and decrease the absorbance at 613 nm, while increase the absorbance at 450 nm, resulting in a fluorescence turn-off and colorimetric spectral response. Moreover, the CDs had short response time of 10 min and high sensitivity towards BPO with a low limit of detection of 28 nmol/L. The applicability of the CDs in detecting BPO in wheat, noodle and starch samples was further demonstrated, and good recovery results were obtained.
A carbon dot (CD)-based fluorescent and colorimetric probe for visually, sensitively and selectively sensing BPO was reported. The addition of BPO could quench the red fluorescence of CDs peaked at 622 and 677 nm, and decrease the absorbance at 613 nm, while increase the absorbance at 450 nm, resulting in a fluorescence turn-off and colorimetric spectral response. The applicability of the CDs in detecting BPO in wheat, noodle and starch samples were further demonstrated, and good recoveries were obtained.
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The regulation of photochemical properties of phototheranostics, especially the absorption, fluorescence, singlet oxygen (1O2) generation, and photothermal conversion efficiency, is a hot research ...topic. Here, we designed and synthesized four boron dipyrromethene (BODIPY) derivatives with high absorption coefficients and intense fluorescence in the near-infrared (NIR) region. The substituted electron-donating group significantly improved 1O2 generation and fluorescence of BODIPYs, whereas the electron-withdrawing group boosts photothermal conversion. These hydrophobic BODIPYs were further coated with DSPE-PEG-2000 to form water dispersible nanoparticles (NPs). Among these BODIPY NPs, the B-OMe-NPs with methoxyl substituted at the meso-position showed the highest 1O2 generation, a photothermal conversion efficiency of 66.5%, and an NIR fluorescence peak at 809 nm. In vitro and in vivo experiments demonstrated that B-OMe-NPs might be used for NIR fluorescent and photoacoustic imaging-guided photodynamic and photothermal therapy of cancer.
Detecting Counterfeit Brandies Wang, Benhua; Han, Jinsong; Zhang, Hao ...
Chemistry : a European journal,
November 22, 2018, Letnik:
24, Številka:
65
Journal Article
Recenzirano
A hypothesis‐free sensor array (optoelectronic tongue) composed of an anionic, a cationic and two neutral poly(para‐aryleneethynylene)s (PAE) at pH 3, 7 and 13 discriminate more than 30 spirits ...(including brandy, Branntwein, Cognac, Spirituose, and Weinbrand). Counterfeits (made by mixing of low‐quality spirits and caramel colour) and different batches of identical brands of brandies are discriminated. The sensor array works without sample preparation or great instrumental cost, and is superior to conventional methods with respect to sample need (10–20 μL), time and effort. The discrimination stems from differential fluorescence quenching of the PAE‐array by the complex mixture of the beverages’ colourants, from the oak barrels or added caramel colour. The collected quenching data were analysed by linear discriminant analysis (LDA) and principal component analysis (PCA) to achieve successful discrimination.
Fake news: Brandies are herein discriminated using hypothesis free sensor arrays. The results are compared to those obtained with classic methods, in which alcohol, density and extract are analysed by GC‐MS and other methods.
We describe a simple optoelectronic tongue, consisting of a positively charged, fluorescent poly(para-phenyleneethynylene), P2, that reacts to fruit juices, when employed at three different pH-values ...(pH 3, 7, 13). This minimal tongue identifies and discriminates 14 different commercially available apple juices, 6 different grape juices and 5 different black currant juices from each other. A similar, negatively charged fluorescent polymer, P1, also achieved discrimination, but the analyte concentration had to be increased by a factor of 50. A mixture of black currant juice and red grape juice is identified as red grape juice, for specific combinations of grape and black currant juices. A mixture of red and green grape juice passes as red grape juice in our sensing system when it contains more than 70% of red grape juice. The data were obtained by fluorescence quenching of the conjugated polymers and processed by linear discriminant analysis of the collected data.
Various phototheranostics have recently been developed for phototherapy. Through proper molecular design, the photochemical and photophysical properties of these phototheranostics can be promoted. ...Herein, an acceptor-donor-acceptor (A-D-A)-structured dye, BTP-4F-DMO, was synthesized and prepared into water-soluble nanoparticles (NPs). The obtained BTP-4F-DMO NPs had strong absorption from 650 nm to 850 nm and a fluorescence emission peak at ∼900 nm that tailed to ∼1100 nm. The NPs showed a superhigh photothermal conversion efficiency of 90.5% ± 5% and could simultaneously generate •OH and 1O2 with a 1O2 generation quantum yield of 4.6% under 808 nm laser irradiation. Due to these advanced properties, BTP-4F-DMO NPs can switch the role of autophagy from pro-survival to pro-death, thereby further promoting cancer cell death. These features make BTP-4F-DMO NPs a promising multifunctional phototheranostic agent for NIR-II fluorescence/photoacoustic dual-mode imaging-guided synergetic photodynamic/photothermal therapy. In general, this work provides a strategy for expanding the biomedical applications of organic A-D-A-structured phototheranostics.
BTP-4F-DMO NPs possess super high photothermal conversion efficacy (90.5% ± 5%) and the ability to produce •OH and 1O2, which greatly enhanced the therapeutic effect and thus induced the pro-death autophagy, both of which make it a promising candidate for its further applications. Display omitted
In biology, non-specific interactions are ubiquitous and important, whereas in chemistry, non-specificity or non-selectivity is suspect. We present simple tongues consisting of fluorescent ...polyelectrolytes or chimeric green fluorescent proteins (GFPs) to discriminating 33 different whiskies according to their country of origin (Ireland, US, or Scotland), brand, blend status (blend or single malt), age, and taste (rich or light). The mechanism of action for these tongues is differential quenching of the fluorescence of the poly(aryleneethynylene)s or the GFPs by the complex mixture of colorants (vanillin, vanillic acid, oak lactones, tannins, etc.; the interactome) extracted from the oak barrels and added caramel coloring. The differential binding and signal generation of the interactomes to the polymers and proteins result from hydrophobic and electrostatic interactions. The collected quenching data, i.e., the response patterns, were analyzed by linear discriminant analysis. Our tongues do not need any sample preparation and are equal or superior to state-of-the-art mass spectrometric methods with respect to speed, resolution, and efficiency of discrimination.
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•Two hypothesis-free sensor arrays discriminate whiskies on the basis of fluorescence modulation•The arrays recognize brand, origin, blending state, age, and taste of the tested whiskies•Non-specific interactions, such as hydrophobics and electrostatics, are operative
The simple discrimination of complex analytes (beverages, foodstuffs, prescription drugs, etc.) is important for economic and health-related reasons. Because one cannot construct specific sensors or assays for analytes such as whiskies, powerful alternative methods are needed. Two hypothesis-free three-element arrays of charged fluorescent dyes (one composed of fluorescent proteins and the other composed of large π systems) differentiate more than 30 whiskies according to their differential fluorescence intensity modulation along the axes of age, area of origin, and taste. Small, arbitrarily selected arrays display a fundamentally important and unexpected power of discrimination for very different analytes, which we will harness in the future to discriminate counterfeit consumer goods (e.g., perfumes and alcoholic beverages) and prescription drugs (outdated, adulterated, counterfeit, brand free, etc.). Such an extension has a direct significant impact on society and some impact on the economy.
We apply two three-element arrays consisting either of different GFPs or of charged fluorescent poly(p-aryleneethynylene)s as a successful, hypothesis-free tongue that discriminates more than 30 whiskies according to their country of origin, brand, blend status, and taste. The underlying mechanism is the modulation of the fluorescence intensity of the elements of the sensor array by the different whiskies. Age, country of origin, blend status, and elements of taste were discriminated by the two very different tongues.
A self‐assembled nine‐element optoelectronic tongue consisting of a positively charged water‐soluble poly(para‐phenyleneethynylene) and three metal ions (Fe2+, Co2+, and Cu2+) at three different pH ...values (7, 10, and 13) discriminates all of the 20 natural amino acids in water. Unknown identification was not ideal. Addition of a highly positively charged green fluorescent protein in the presence of Fe2+, Co2+, and Cu2+ increased the unknown identification to above 86 %. Linear discriminant analysis (LDA) orders the responses according to the amino acid type, that is, hydrophobic, polar, anionic, or cationic.
Metals make the difference: Self‐assembled optoelectronic tongues consisting of a positively charged water‐soluble poly(para‐phenyleneethynylene) polymer or a fluorescent protein with a supercharged tag and three metal ions (Fe2+, Co2+, and Cu2+) at three different pH values discriminate all of the 20 natural amino acids in water (see scheme).
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