Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Caging metal ions with visible light-responsive nanopolymersomes.

ABSTRACT: Polymersomes are bilayer vesicles that self-assemble from amphiphilic diblock copolymers, and provide an attractive system for the delivery of biological and nonbiological molecules due to their environmental compatibility, mechanical stability, synthetic tunability, large aqueous core, and hyperthick hydrophobic membrane. Herein, we report a nanoscale photoresponsive polymersome system featuring a meso-to-meso ethyne-bridged bis[(porphinato)zinc] (PZn2) fluorophore hydrophobic membrane solute and dextran in the aqueous core. Upon 488 nm irradiation in solution or in microinjected zebrafish embryos, the polymersomes underwent deformation, as monitored by a characteristic red-shifted PZn2 emission spectrum and confirmed by cryo-TEM. The versatility of this system was demonstrated through the encapsulation and photorelease of a fluorophore (FITC), as well as two different metal ions, Zn(2+) and Ca(2+).

SUBMITTER: Griepenburg JC

PROVIDER: S-EPMC4303334 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Caging metal ions with visible light-responsive nanopolymersomes.

Griepenburg Julianne C JC Sood Nimil N Vargo Kevin B KB Williams Dewight D Rawson Jeff J Therien Michael J MJ Hammer Daniel A DA Dmochowski Ivan J IJ

Langmuir : the ACS journal of surfaces and colloids 20150107 2

Polymersomes are bilayer vesicles that self-assemble from amphiphilic diblock copolymers, and provide an attractive system for the delivery of biological and nonbiological molecules due to their environmental compatibility, mechanical stability, synthetic tunability, large aqueous core, and hyperthick hydrophobic membrane. Herein, we report a nanoscale photoresponsive polymersome system featuring a meso-to-meso ethyne-bridged bis[(porphinato)zinc] (PZn2) fluorophore hydrophobic membrane solute a ...[more]

PMID: 25518002

Similar Datasets

Photoefficient 2nd generation molecular motors responsive to visible light.

Project description:Molecular motors that operate with high efficiency using visible light are attractive for numerous applications. Here the synthesis and characterisation of three novel visible light switchable 2nd generation molecular motors is presented. Two of them are based on push-pull systems with the third one possessing an extended ?-system. With a maximum effective excitation wavelength of 530 nm we designed the most red-shifted artificial rotary motor known to date. All three motors benefit from efficient switching to the metastable isomer, high quantum yields and excellent photostability setting them apart from visible light switchable motors reported previously. The activation barriers of the rate-determining thermal helix inversion could be accurately predicted using DFT calculations and differences between the motors can be explained by distinct transition state structures. Enantiomers of push-pull motors were successfully separated and their helical twisting power in E7 liquid crystals was determined.

| S-EPMC6849633 | biostudies-literature

Visible-Light Responsive Sucrose-Containing Macrocyclic Host for Cations.

Project description:Chiral photoresponsive host 1 was prepared by a high-yield Cs2CO3-templated macrocyclization. Trans-1 transforms into long-lived cis-1 (25 days) upon irradiation with green light, and the backward transformation is triggered by blue light. Both isomers prefer potassium among alkali metal cations, and cis-1 binds cations stronger than trans-1 (Kcis/Ktrans ≤ 4.1). 1H NMR titration experiments as well as density functional theory studies reveal that sucrose ring oxygen residues and azobenzene nitrogen atoms in 1 contribute to cation coordination.

| S-EPMC8041374 | biostudies-literature

Photocatalytic Hydrogen Generation from a Visible-Light-Responsive Metal-Organic Framework System: Stability versus Activity of Molybdenum Sulfide Cocatalysts.

Project description:We report the use of two earth abundant molybdenum sulfide-based cocatalysts, Mo3S132- clusters and 1T-MoS2 nanoparticles (NPs), in combination with the visible-light active metal-organic framework (MOF) MIL-125-NH2 for the photocatalytic generation of hydrogen (H2) from water splitting. Upon irradiation (? ? 420 nm), the best-performing mixtures of Mo3S132-/MIL-125-NH2 and 1T-MoS2/MIL-125-NH2 exhibit high catalytic activity, producing H2 with evolution rates of 2094 and 1454 ?mol h-1 gMOF-1 and apparent quantum yields of 11.0 and 5.8% at 450 nm, respectively, which are among the highest values reported to date for visible-light-driven photocatalysis with MOFs. The high performance of Mo3S132- can be attributed to the good contact between these clusters and the MOF and the large number of catalytically active sites, while the high activity of 1T-MoS2 NPs is due to their high electrical conductivity leading to fast electron transfer processes. Recycling experiments revealed that although the Mo3S132-/MIL-125-NH2 slowly loses its activity, the 1T-MoS2/MIL-125-NH2 retains its activity for at least 72 h. This work indicates that earth-abundant compounds can be stable and highly catalytically active for photocatalytic water splitting, and should be considered as promising cocatalysts with new MOFs besides the traditional noble metal NPs.

| S-EPMC6137427 | biostudies-literature

Ce-Doped Graphitic Carbon Nitride Derived from Metal Organic Frameworks as a Visible Light-Responsive Photocatalyst for H2 Production.

Project description:Novel fibrous graphitic carbon nitride (g-C3N4) derivatives prepared from metal organic frameworks (MOFs) were doped with Ce3+ (Ce-C3N4) as photocatalytic materials. Ce-C3N4 was characterized using various techniques, revealing its high specific surface area, excellent photocatalytic activity, and stability for H2 evolution under visible light irradiation. The fluorine modified samples show superior photocatalytic activity under visible light irradiation, which is due to the presence of more active sites and enhanced absorption of solar energy. This work provides a new synthetic route for MOF-derived g-C3N4 that can be doped with different metal ions. The fluorine modified Ce-C3N4 is an efficient photocatalyst with potential for many applications related to energy and the environment.

| S-EPMC6915336 | biostudies-literature

Visible light mediated metal-free thiol-yne click reaction.

Project description:The carbon-sulfur bond formation reaction is of paramount importance for functionalized materials design, as well as for biochemical applications. The use of expensive metal-based catalysts and the consequent contamination with trace metal impurities are challenging drawbacks of the existing methodologies. Here, we describe the first environmentally friendly metal-free photoredox pathway to the thiol-yne click reaction. Using Eosin Y as a cheap and readily available catalyst, C-S coupling products were obtained in high yields (up to 91%) and excellent selectivity (up to 60 : 1). A 3D-printed photoreactor was developed to create arrays of parallel reactions with temperature stabilization to improve the performance of the catalytic system.

| S-EPMC5355861 | biostudies-literature

Enhanced Visible-Light-Responsive Photocatalytic Degradation of Ciprofloxacin by the Cu<sub>x</sub>O/Metal-Organic Framework Hybrid Nanocomposite.

Project description:Ciprofloxacin (CIP) is a commonly used antibiotic, however, once in the environment, it is highly toxic with a poor biodegradability. Given these attributes, an effective strategy for the removal of CIP is urgently needed for the protection of water resources. Herein, a novel copper metal-organic framework (CuxO/MOF) multifunctional material has been produced, in this work, by the calcination of Cu-MOF urea at 300 °C, in the presence of a 5% H2 atmosphere. The morphological, structural, and thermal properties of the prepared CuxO/MOF were determined through various techniques, and its photocatalytic behavior was investigated for the degradation of CIP under visible-light irradiation. The prepared CuxO/MOF bifunctional material is presented as a graphitic carbon-layered structure with a particle size of 9.2 ± 2.1 nm. The existence of CuO-Cu2O-C, which was found on the CuxO/MOF surface, enhanced the adsorption efficiency and increased the photosensitivity of CuxO/MOF, towards the degradation of CIP in aqueous solutions. The tailored CuxO/MOF, not only shows an excellent CIP degradation efficiency of up to 92% with a constant kinetic rate (kobs) of 0.048 min-1 under visible light, but it can also retain the stable photodegradation efficiency of >85%, for at least six cycles. In addition, CuxO/MOF has an excellent adsorption capacity at pH 6.0 of the maximum Langmuir adsorption capacity of 34.5 mg g-1 for CIP. The results obtained in this study demonstrate that CuxO/MOF is a reliable integrated material and serves as an adsorbent and photocatalyst, which can open a new pathway for the preparation of visible-light-responsive photocatalysts, for the removal of antibiotics and other emerging pollutants.

| S-EPMC9864703 | biostudies-literature

HOCl Responsive Lanthanide Complexes Using Hydroquinone Caging Units.

Project description:Redox biology is still looking for tools to monitor redox potential in cellular biology and, despite a large and sustained effort, reliable molecular probes have yet to emerge. In contrast, molecular probes for reactive oxygen and nitrogen have been widely explored. In this manuscript, three kinetically inert lanthanide complexes that selectively react with hypochlorous acid are prepared and characterized. The design is based on 1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid (DO3A) and 1,4,7,10-tetraazacyclododecane-1,7-diacetic acid (DO2A) ligands appended with one or two redox active hydroquinone derived arms, thereby forming octadentate ligands ideally suited to complex trivalent lanthanide ions. The three complexes are found to react selectively with hypochlorous acid to form highly symmetric lanthanide(III) 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacedic acid (DOTA) complexes. The conversion of the probe to [Ln.DOTA]- is followed by luminescence, absorption, and NMR spectroscopy in a model system comprised of a Triton-X modified HEPES buffer. It was concluded that the design principle works, and that simple caging units like hydroquinones can work well in conjugation with lanthanide(III) complexes.

| S-EPMC7221670 | biostudies-literature

Two-Step, One-Pot Synthesis of Visible-Light-Responsive 6-Azopurines.

Project description:The first general two-step, one-pot synthetic route to 6-azopurines is presented. Microwave-assisted nucleophilic aromatic substitution of protected 6-chloropurines with hydrazines or hydrazides, followed by metal-free oxidation with oxygen, gives 6-azopurines in high to excellent yields. Photophysical studies revealed intensive n-?* absorption band that makes trans-to-cis photoswitching possible using visible light (? = 530 nm).

| S-EPMC5633830 | biostudies-literature

Visible Light Induced Metal-Free Carbene <i>N</i>-Carbazolation.

Project description:Metal-free N-H functionalization reactions represent an important strategy for sustainable C-N coupling reactions. In this report, we describe the visible light photolysis of aryl diazoacetates in the presence of some N-heterocycles that enables mild, metal-free N-H functionalization reactions of carbazole and azepine heterocycles (15 examples, up to 83% yield).

| S-EPMC6900254 | biostudies-literature

Visible light-promoted metal-free sp(3)-C-H fluorination.

Project description:Photoexcited acetophenone can catalyze the fluorination of unactivated C(sp(3))-H groups. While acetophenone, a colorless oil, only has a trace amount of absorption in the visible light region, its photoexcitation can be achieved by irradiation with light generated by a household compact fluorescent lamp (CFL). This operational simple method provides improved substrate scope for the direct incorporation of a fluorine atom into simple organic molecules. CFL-irradiation can also be used to promote certain classic UV-promoted photoreactions of colorless monoarylketones and enones/enals.

| S-EPMC4160356 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data