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ChemPlusChem Nov 2023Transition metal phosphides are promising, selective, and air-stable nanocatalysts for hydrogenation reactions. However, they often require fairly high temperatures and...
Transition metal phosphides are promising, selective, and air-stable nanocatalysts for hydrogenation reactions. However, they often require fairly high temperatures and H pressures to provide quantitative conversions. This work reports the positive effect of phosphine additives on the activity of cobalt phosphide nano-urchins for the semi-hydrogenation of phenylacetylene. While the nanocatalyst's activity was low under mild conditions (7 bar of H , 100 °C), the addition of a catalytic amount of phosphine remarkably increased the conversion, e. g., from 13 % to 98 % in the case of P Bu . The heterogeneous nature of the catalyst was confirmed by negative supernatant activity tests. The catalyst integrity was carefully verified by post-mortem analyses (TEM, XPS, and liquid P NMR). A stereo-electronic map was proposed to rationalize the activity enhancement provided over a selection of nine phosphines: the strongest effect was observed for low to moderately hindered phosphines, associated with strong electron donor abilities. A threshold in phosphine stoichiometry was revealed for the enhancement of activity to occur, which was related to the ratio of phosphine to surface cobalt atoms.
PubMed: 37694531
DOI: 10.1002/cplu.202300469 -
Bioorganic & Medicinal Chemistry Letters May 2021Innovative organogold(I) antibacterial compounds were synthesized by click chemistry with triethylphosphine-gold(I) azides and an alkyne derivative. The resulting...
Innovative organogold(I) antibacterial compounds were synthesized by click chemistry with triethylphosphine-gold(I) azides and an alkyne derivative. The resulting organo-gold(I) compounds exhibit high levels of antibacterial activity against Gram-positive pathogens, with particularly low MICs against Clostridium difficile.
Topics: Alkynes; Anti-Bacterial Agents; Azides; Catalysis; Click Chemistry; Clostridioides difficile; Cycloaddition Reaction; Drug Discovery; Drug Resistance; Enterococcus; Escherichia coli; Humans; Microbial Sensitivity Tests; Organogold Compounds; Phosphines; Staphylococcus; Triazoles
PubMed: 33636306
DOI: 10.1016/j.bmcl.2021.127879 -
Journal of the American Chemical Society Feb 2021The development of fluorescent dyes that emit and absorb light at wavelengths greater than 700 nm and that respond to biochemical and biophysical events in living...
The development of fluorescent dyes that emit and absorb light at wavelengths greater than 700 nm and that respond to biochemical and biophysical events in living systems remains an outstanding challenge for noninvasive optical imaging. Here, we report the design, synthesis, and application of near-infrared (NIR)-absorbing and -emitting optical voltmeter based on a sulfonated, phosphine-oxide (po) rhodamine for voltage imaging in intact retinas. We find that po-rhodamine based voltage reporters, or poRhoVRs, display NIR excitation and emission profiles at greater than 700 nm, show a range of voltage sensitivities (13 to 43% ΔF/F per 100 mV in HEK cells), and can be combined with existing optical sensors, like Ca-sensitive fluorescent proteins (GCaMP), and actuators, like light-activated opsins ChannelRhodopsin-2 (ChR2). Simultaneous voltage and Ca imaging reveals differences in activity dynamics in rat hippocampal neurons, and pairing poRhoVR with blue-light based ChR2 affords all-optical electrophysiology. In retinas isolated from a mouse model of retinal degeneration, poRhoVR, together with GCaMP-based Ca imaging and traditional multielectrode array (MEA) recording, can provide a comprehensive physiological activity profile of neuronal activity, revealing differences in voltage and Ca dynamics within hyperactive networks of the mouse retina. Taken together, these experiments establish that poRhoVR will open new horizons in optical interrogation of cellular and neuronal physiology in intact systems.
Topics: Animals; Calcium; Fluorescent Dyes; Infrared Rays; Mice; Neurons; Optical Imaging; Oxides; Phosphines; Retina; Rhodamines
PubMed: 33501825
DOI: 10.1021/jacs.0c11382 -
Journal of Chromatography. A Jan 2021The reliable determination of arsine (AsH) and phosphine (PH) in hydrogen (H), nitrogen (N) and liquefied petroleum gas (LPG) is of great importance because of its... (Review)
Review
Development and validation of a methodology for quantifying parts-per-billion levels of arsine and phosphine in nitrogen, hydrogen and liquefied petroleum gas using a variable pressure sampler coupled to gas chromatography-mass spectrometry.
The reliable determination of arsine (AsH) and phosphine (PH) in hydrogen (H), nitrogen (N) and liquefied petroleum gas (LPG) is of great importance because of its drastic effects on the efficiency of catalysts, as well as the strict regulations associated with health, safety and environmental issues. It is challenging for an analyst to determine the parts per billion of AsH and PH in H, N, and LPG at low and high pressures without collection procedures using adsorption, desorption, and dissolution techniques. To overcome this analytical need an analytical methodology was developed, employing a variable pressure sampler (VPS) coupled to a gas chromatograph (GC) with mass spectrometry (MS) for the identification and quantification of traces of AsH and PH. The instrumentation, tubing and accessories of the VPS were made of passivated steel to avoid losses from absorption of AsH and PH in the steel which would generate significant analytical problems. The VPS had a homogeneous heating block that prevented analyte losses from condensation. With the VPS, 24 AsH and PH standards were prepared between 0.005 and 0.1 mg kg in balance of H, N and LPG. The separation and quantification of the analytes was achieved with an improved GC with 4 valves and 5 columns in series that guaranteed the elimination of impurities. The proposed method was optimized in VPS and GC-MS and then validated showing highly accaptable linearity (r > 0.9999), detection limits (<0.0009 mg kg), limits of quantification (<0.003 mg kg), intra-day and inter-day precision and accuracy (<1.14% and ≤3.0% respectively), recovery for the standard addition (86-109%), P values> 0.05 for the test Student's t paired who evaluated the effect of the matrix on pressure and concentration. The speed of analysis was high (<5.2 min). The method was applied to real samples, showing values between 0.005 and 0.1 mg kg and an effect on the efficiency of the Ziegler Natta catalyst between 5 and 56%.
Topics: Arsenicals; Gas Chromatography-Mass Spectrometry; Humans; Hydrogen; Limit of Detection; Nitrogen; Petroleum; Phosphines; Reproducibility of Results
PubMed: 33373796
DOI: 10.1016/j.chroma.2020.461833 -
Astrobiology Oct 2021The recent candidate detection of ∼1 ppb of phosphine in the middle atmosphere of Venus is so unexpected that it requires an exhaustive search for explanations of its...
The recent candidate detection of ∼1 ppb of phosphine in the middle atmosphere of Venus is so unexpected that it requires an exhaustive search for explanations of its origin. Phosphorus-containing species have not been modeled for Venus' atmosphere before, and our work represents the first attempt to model phosphorus species in the venusian atmosphere. We thoroughly explore the potential pathways of formation of phosphine in a venusian environment, including in the planet's atmosphere, cloud and haze layers, surface, and subsurface. We investigate gas reactions, geochemical reactions, photochemistry, and other nonequilibrium processes. None of these potential phosphine production pathways is sufficient to explain the presence of ppb phosphine levels on Venus. If PH's presence in Venus' atmosphere is confirmed, it therefore is highly likely to be the result of a process not previously considered plausible for venusian conditions. The process could be unknown geochemistry, photochemistry, or even aerial microbial life, given that on Earth phosphine is exclusively associated with anthropogenic and biological sources. The detection of phosphine adds to the complexity of chemical processes in the venusian environment and motivates follow-up sampling missions to Venus. Our analysis provides a template for investigation of phosphine as a biosignature on other worlds.
Topics: Atmosphere; Extraterrestrial Environment; Phosphines; Venus
PubMed: 34283644
DOI: 10.1089/ast.2020.2352 -
Nederlands Tijdschrift Voor Geneeskunde Mar 2023Toxic inhalations form a rare cause of poisoning in the Netherlands. The initial symptoms of toxic inhalations may appear similar to acute viral infections. In the...
BACKGROUND
Toxic inhalations form a rare cause of poisoning in the Netherlands. The initial symptoms of toxic inhalations may appear similar to acute viral infections. In the maritime sector aluminum or zinc phosphide is used to overcome rodent infestations during transportation.
CASE DESCRIPTION
Here we discuss two patients intoxicated with gaseous phosphide used as fumigant in the transport of grains. The exposure to phosphide gas resulted in respiratory and gastrointestinal tract symptoms. Upon admission one of the patients deteriorated resulting in respiratory insufficiency, multi-organ failure and cardiogenic shock.
CONCLUSION
Phosphide gas poisoning forms a rare cause for transient acute heart and multiorgan failure largely due to mitochondria dysfunction. In the case of unexplained incapacitation of multiple patients and/or pets toxic inhalations should differentially diagnostically be considered.
Topics: Humans; Gastrointestinal Diseases; Multiple Organ Failure; Phosphines; Poisoning; Shock, Cardiogenic
PubMed: 36928812
DOI: No ID Found -
Chembiochem : a European Journal of... Dec 2021Cellular senescence, a stable form of cell cycle arrest, facilitates protection from tumorigenesis and aids in tissue repair as they accumulate in the body at an early...
Cellular senescence, a stable form of cell cycle arrest, facilitates protection from tumorigenesis and aids in tissue repair as they accumulate in the body at an early age. However, long-term retention of senescent cells causes inflammation, aging of the tissue, and progression of deadly diseases such as obesity, diabetes, and atherosclerosis. Various attempts have been made to achieve selective elimination of senescent cells from the body, yet little has been explored in designing the mitochondria-targeted senolytic agent. Many characteristics of senescence are associated with mitochondria. Here we have designed a library of alkyl-monoquaternary ammonium-triphenyl phosphine (TPP) and alkyl-diquaternary ammonium-TPP of varying alkyl chain lengths, which target the mitochondria; we also studied their senolytic properties. It was observed that the alkyl-diquaternary ammonium-TPP with the longest chain length induced apoptosis in senescent cells selectively via an increase of reactive oxygen species (ROS) and mitochondrial membrane disruption. This study demonstrates that mitochondria could be a potential target for designing new small molecules as senolytic agents for the treatment of a variety of dysfunctions associated with pathological aging.
Topics: Ammonium Compounds; Animals; Antineoplastic Agents; Apoptosis; Benzene Derivatives; Cell Survival; Cellular Senescence; Drug Screening Assays, Antitumor; HEK293 Cells; Humans; Mice; Mitochondrial Membranes; Molecular Structure; NIH 3T3 Cells; Phosphines
PubMed: 34580971
DOI: 10.1002/cbic.202100412 -
Scientific Reports Aug 2019The reaction of gold reagents [HAuCl•3HO], [AuCl(tht)], or cyclometalated gold(III) precursor, [C^NAuCl] with chiral ((R,R)-(-)-2,3-bis(t-butylmethylphosphino)...
The reaction of gold reagents [HAuCl•3HO], [AuCl(tht)], or cyclometalated gold(III) precursor, [C^NAuCl] with chiral ((R,R)-(-)-2,3-bis(t-butylmethylphosphino) quinoxaline) and non-chiral phosphine (1,2-Bis(diphenylphosphino)ethane, dppe) ligands lead to distorted Au(I), (1, 2, 4, 5) and novel cyclometalated Au(III) complexes (3, 6). These gold compounds were characterized by multinuclear NMR, microanalysis, mass spectrometry, and X-ray crystallography. The inherent electrochemical properties of the gold complexes were also studied by cyclic voltammetry and theoretical insight of the complexes was gained by density functional theory and TD-DFT calculations. The complexes effectively kill cancer cells with IC in the range of ~0.10-2.53 μΜ across K562, H460, and OVCAR8 cell lines. In addition, the retinal pigment epithelial cell line, RPE-Neo was used as a healthy cell line for comparison. Differential cellular uptake in cancer cells was observed for the compounds by measuring the intracellular accumulation of gold using ICP-OES. Furthermore, the compounds trigger early - late stage apoptosis through potential disruption of redox homeostasis. Complexes 1 and 3 induce predominant G1 cell cycle arrest. Results presented in this report suggest that stable gold-phosphine complexes with variable oxidation states hold promise in anticancer drug discovery and need further development.
Topics: Animals; Apoptosis; Cattle; Cell Cycle; Cell Death; Cell Line, Tumor; Cell Proliferation; Crystallography, X-Ray; Density Functional Theory; Electrochemistry; Electrodes; Endocytosis; Gold; Humans; Inhibitory Concentration 50; Magnetic Resonance Spectroscopy; Models, Molecular; Phosphines; Serum Albumin, Bovine; Serum Albumin, Human; Spectrophotometry, Ultraviolet; Temperature
PubMed: 31451718
DOI: 10.1038/s41598-019-48584-5 -
Bioorganic & Medicinal Chemistry Letters Oct 2020The development of both chemotherapeutic drug resistance as well as adverse side effects suggest that the current chemotherapeutic drugs remain ineffective in treating...
The development of both chemotherapeutic drug resistance as well as adverse side effects suggest that the current chemotherapeutic drugs remain ineffective in treating the various types of cancers. The development of new metallodrugs presenting anti-cancer activity is therefore needed. Ruthenium complexes have gained a great deal of interest due to their promising anti-tumour properties and reduced toxicity in vivo. This study highlighted the effective induction of cell death in a malignant melanoma cell by two novel bis-amino-phosphine ruthenium(II) complexes referred to as GA105 and GA113. The IC concentrations were determined for both the complexes, the ligand and cisplatin, for comparison. Both complexes GA105 and GA113 displayed a high anti-cancer selectivity profile as they exhibited low IC values of 6.72 µM and 8.76 µM respectively, with low toxicity towards a non-malignant human cell line. The IC values obtained for both complexes were lower than that of cisplatin. The new complexes were more effective compared to the free ligand, GA103 (IC = >20 µM). Morphological studies on treated cells induced apoptotic features, which with further studies could indicate an intrinsic cell death pathway. Additionally, flow cytometric analysis revealed that the mode of cell death of complex GA113 was apoptosis. The outcomes herein give further insight into the potential use of selected Ru(II) complexes as alternative chemotherapeutic drugs in the future.
Topics: Antineoplastic Agents; Cell Proliferation; Cell Survival; Coordination Complexes; Diamines; Dose-Response Relationship, Drug; Drug Screening Assays, Antitumor; HEK293 Cells; Humans; Ligands; Molecular Structure; Phosphines; Ruthenium; Structure-Activity Relationship
PubMed: 32791194
DOI: 10.1016/j.bmcl.2020.127492 -
Journal of Inorganic Biochemistry Sep 2021The use of natural products as potential ligands has been explored as a strategy in the development of metal-based chemotherapy. Since ruthenium complexes are promising...
The use of natural products as potential ligands has been explored as a strategy in the development of metal-based chemotherapy. Since ruthenium complexes are promising alternatives to traditional antitumor agents, this study evaluated the anti-melanoma potential of two ruthenium(II) complexes containing the naphthoquinone ligands lapachol (lap), [Ru(lap)(dppm)]PF, and lawsone (law), [Ru(law)(dppm)]PF, in addition to the bis(diphenylphosphino)methane (dppm) ligand, referred to as complexes (1) and (2), respectively, using a syngeneic murine melanoma model. Activation of the apoptotic pathway by the treatments was assessed by immunohistochemistry in tumor tissue. Additionally, toxicity of the treatments was evaluated by variation in body and organ weight, quantification of biochemical indicators of renal damage, and genotoxicity in bone marrow and hepatocytes. First, the antiproliferative activity of (1) and (2) was observed in B16F10 cells, with IC values of 2.78 and 1.68 μM, respectively. The results obtained in mice showed that, unlike complex (1), (2) possesses significant anti-melanoma activity demonstrated by a reduction in tumor volume and mass (88.42%), as well as in mitosis frequency (83.86%). Additionally, complex (2) increased the levels of cleaved caspase-3, inducing tumor cell apoptosis. When compared to the metallodrug cisplatin, complex (2) exhibited similar anti-melanoma activity and lower toxicity considering all parameters evaluated. In silico studies demonstrated no difference in the binding energy of the naphthoquinone complex between complexes (1) and (2). However, the complex containing the lawsone ligand has a lower molar volume, which may be important for interactions with minor DNA grooves. The present results demonstrate the antitumor efficiency of complex (2) and a significantly lower systemic toxicity compared to cisplatin.
Topics: Animals; Antineoplastic Agents; Cell Line, Tumor; Cell Proliferation; Coordination Complexes; Ligands; Male; Melanoma; Mice, Inbred C57BL; Naphthoquinones; Phosphines; Ruthenium; Mice
PubMed: 34090039
DOI: 10.1016/j.jinorgbio.2021.111497