One-pot Aqueous Synthesis Research Articles

Ring-opening metathesis polymerization-induced self-assembly (ROMPISA) of a cisplatin analogue for high drug-loaded nanoparticles

We report the one-pot aqueous phase synthesis of cisplatin drug loaded micellar nanoparticles using Ring-Opening Metathesis Polymerization-Induced Self-Assembly (ROMPISA).

One-pot aqueous synthesis of ultrathin trimetallic PdPtCu nanosheets for the electrooxidation of alcohols

Ultrathin PdPtCu nanosheets were prepared by a facile, eco-friendly, and low-cost synthetic method and exhibited remarkably enhanced performances towards various electrocatalytic alcohol oxidations due to synergistic structural and compositional advantages.

Multivariate optimization of optical properties of CdSe quantum dots obtained by a facile one-pot aqueous synthesis

Four parameters are simultaneously optimized to provide a simple, fast and reproducible synthesis procedure to obtain high-quality CdSe quantum dots.

Carbon nanospheres with dual-color emission and their application in ratiometric pyrophosphate sensing.

Herein, we employ pH-dependent solubility equilibrium to develop the one-pot aqueous synthesis of dual-color emission fluorescent carbon nanosphere (DFCSs) with novel physicochemical properties. Unexpectedly, some of the DFCSs have a regular nanosphere shape, containing uniform carbon dots (∼20 nm) on their surface. This may be attributed to the change in the surface composition of the carbon nanospheres under the strong alkaline conditions (pH 13), which results in dual-wavelength emission by single-wavelength excitation. Interestingly, the fluorescence intensities of the two emission peaks of the DFCSs at 315/410 nm can be simultaneously quenched upon the addition of Co2+ due to the strong coordination between Co2+ and the O-containing luminescent groups from the carbon dots and DFCSs. Also, the results demonstrate that one Co2+ simultaneously combines with two chromophoric groups. Furthermore, the quenched DFCSs exhibit high sensitivity for pyrophosphate (PPi) in the range of 0.075-200.0 μM through a fluorescence recovery process, which can be attributed to the stronger Co2+-O[double bond, length as m-dash]P bond. This results in the removal of Co2+ from the surface of DFCSs-Co2+ system via competitive adsorption interactions. Meanwhile, this sensor shows high selectivity for PPi over mercapto amino acid and phosphate in aqueous solution. These results indicate the DFCSs can act as a dual-signal PPi-selective sensor via a ratiometric competitive mechanism.

Aqueous one-pot synthesis of epoxy-functional diblock copolymer worms from a single monomer: new anisotropic scaffolds for potential charge storage applications

The one-pot synthesis of highly anisotropic epoxy-functional diblock copolymer worms is achieved directly in water using a single monomer (glycidyl methacrylate).

Dual functionalized, stable and water dispersible CdTe quantum dots: Facile, one-pot aqueous synthesis, optical tuning and energy transfer applications

We report a facile one-pot synthesis of aqueously dispersible CdTe quantum dots (QDs) with tunable optical properties by using dual capping agents namely MPA and Citric acid. Optimum precursor ratio and pH > 8 at 80 °C facilitated particle size tunability and exceptional optical properties. QDs are ∼3.7 nm as seen from HR-TEM image; highly-luminescent showing absolute quantum-yield up to 54% and bear good photostability. CdTe QDs are highly stable in water with large negative Zeta potential. Optimum ratio of Cd2+:MPA:TeO32−:NaBH4:citric acid was 1:2:0.2:3.2:5.2, respectively. The pH dependent nucleation and growth of QDs subsequently lead to quasi CdTe/CdS structure as indicated by XRD, FTIR and particle size analysis. QDs showed excitation independent emission with tunable peak width. QDs can be stored over 6-months at 4 °C without causing agglomeration. Interaction of QDs with Rhodamine-6G and plasmonic silver nanoparticles via resonance energy transfer (RET) imply their suitability for sensors and biomedical applications.

One-pot synthesis of GSH-Capped CdTe quantum dots with excellent biocompatibility for direct cell imaging

In this work, we have developed one-pot aqueous synthesis of glutathione (GSH) binding CdTe quantum dots (QDs) for cell imaging. UV-Vis absorption spectrum, Fourier transform infrared spectrum, photoluminescence spectrum, and high-resolution transmission electron microscopy are applied to characterize the physical and chemical properties of the nanocomposites. The bioimaging efficiency of the GSH-capped CdTe QDs is further evaluated on Hela cells. The groups on the surface of QDs are able to bind to basic proteins, which are abundant in cell nuclei, enabling the application of QDs for direct cell imaging. Experimental results also indicate the GSH layer on the surface of QDs is able to reduce the cytotoxicity significantly. In conclusion, the as-prepared GSH-capped QDs are highly promising fluorescent probes for cell imaging in the near future.

One-Pot Aqueous Synthesis of Nucleoside-Templated Fluorescent Copper Nanoclusters and Their Application for Discrimination of Nucleosides.

A facile, one-pot synthetic method has been proposed to prepare water-soluble fluorescent copper nanoclusters (CuNCs) templated by nucleosides. The nucleoside-templated fluorescent CuNCs were further characterized by using various analytical techniques, such as transmission electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and fluorescence spectroscopy. The role of various reactants such as ascorbic acid, nucleoside, and citrate buffer in the synthesis process of fluorescent CuNCs was explored. The results showed that nucleoside and ascorbic acid were very likey to respectively act as a stabilizer and a reductant to form nanoclusters, and citrate buffer acted as both pH regulator solution and a reducing agent. The fluorescence spectra of various nucleoside-templated CuNCs were finally combined with multivariate chemometrics analysis for discrimination of different nucleosides.

Simple one-pot aqueous synthesis of AuPd alloy nanocrystals/reduced graphene oxide as highly efficient and stable electrocatalyst for oxygen reduction and hydrogen evolution reactions

Herein, we develop a simple one-pot aqueous method to prepare AuPd alloy nanocrystals on reduced graphene oxide (AuPd NCs/rGO), by using 1-acetyl-4-(p-hydroxyphenyl) piperazine (AHPP) as the reductant, stabilizing agent and structure-director, without any other additives (e.g., seed, surfactant or polymer). The product is mainly characterized by transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction and thermogravimetric analysis. The obtained AuPd NCs/rGO displays enlarged electrochemically active surface area and superior catalytic performances toward oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) relative to Pt/C, Pd/C, Pd/rGO and Au/rGO catalysts, showing promising applications in energy storage and conversion.

One-Pot Aqueous Synthesis of Fluorescent Ag-In-Zn-S Quantum Dot/Polymer Bioconjugates for Multiplex Optical Bioimaging of Glioblastoma Cells.

Cancer research has experienced astonishing advances recently, but cancer remains a major threat because it is one of the leading causes of death worldwide. Glioblastoma (GBM) is the most malignant brain tumor, where the early diagnosis is vital for longer survival. Thus, this study reports the synthesis of novel water-dispersible ternary AgInS2 (AIS) and quaternary AgInS2-ZnS (ZAIS) fluorescent quantum dots using carboxymethylcellulose (CMC) as ligand for multiplexed bioimaging of malignant glioma cells (U-87 MG). Firstly, AgInS2 core was prepared using a one-pot aqueous synthesis stabilized by CMC at room temperature and physiological pH. Then, an outer layer of ZnS was grown and thermally annealed to improve their optical properties and split the emission range, leading to core-shell alloyed nanostructures. Their physicochemical and optical properties were characterized, demonstrating that luminescent monodispersed AIS and ZAIS QDs were produced with average sizes of 2.2 nm and 4.3 nm, respectively. Moreover, the results evidenced that they were cytocompatible using in vitro cell viability assays towards human embryonic kidney cell line (HEK 293T) and U-87 MG cells. These AIS and ZAIS successfully behaved as fluorescent nanoprobes (red and green, resp.) allowing multiplexed bioimaging and biolabeling of costained glioma cells using confocal microscopy.

Zeolitic imidazolate framework-8 (ZIF-8) as a sacrificial template: one-pot synthesis of hollow poly(dopamine) nanocapsules and yolk-structured poly(dopamine) nanocomposites

Hollow poly(dopamine) (PDA) nanocapsules and yolk-structured PDA nanocomposites were prepared by an aqueous one-pot synthesis method utilizing zeolitic imidazolate framework-8 (ZIF-8) nanocrystals as a sacrificial template without any special etchant. The resulting PDA nanocapsules show negligible cytotoxicity in HeLa cells after incubation for 48 h at various doses, which implies their potential as candidates for practical applications in drug transport and targeting.

A high yield one-pot aqueous synthesis of crystalline SnO2 nanoparticles

A high temperature thermal treatment after precipitation from an aqueous solution is usually required to reach crystalline SnO2 nanoparticles but this treatment generates a grain growth (up to 40nm). Moreover, the yield is generally low (<80%). In this paper, a new high yield one-pot aqueous synthesis of crystalline SnO2 nanoparticles is described. The synthesis is performed at 100°C under reflux: it exhibits a reaction yield over 90% and the particles are crystallized with a size of 4–6nm.

Observing Ultra-Small Gold Cluster to Plasmonic Nanoparticle Evolution in a One-Pot Aqueous Synthesis

Studies of metal nanoclusters can provide valuable information on how various properties evolve in the nanoscale materials. Previously often mixed-sized products have been separated in order to study their size-related properties. We present here a one-pot aqueous synthesis protocol that allows direct observations of the evolutions of size-dependent optical and electrochemical properties of the gold nanoclusters while the clusters grow from a few-atom, ultra-small size to the plasmonic nanoparticle stage. Our selection of a mixed ligand system comprising of methionine and CTAB for the aqueous synthesis of gold nanoclusters by the chemical reduction of gold ions led to the slow growth of the nanoclusters making direct observations of the cluster growth and concomitant evolution of properties possible. UV-visible spectrophotometric and dynamic light scattering studies demonstrated the size-dependent transition from the molecule-like, non-plasmonic to plasmonic properties in the evolving nanoclusters. Differential pulse voltammetry studies demonstrated how the electrochemical properties changed from the molecule-like redox behavior to a quantized double-layer charging type with the growth of the nanocluster with time. Thermogravimetric analysis, MALDI-TOF mass spectrometry, etc. were employed to further characterize the nanocluster systems. This report will inspire further studies in understanding the evolution of the size-dependent properties of the nanoscale materials.

One-Pot Aqueous Phase Synthesis of CdTe and CdTe/ZnS Core/Shell Quantum Dots.

A facile and economical one-pot strategy has been developed for the synthesis of water-solute CdTe and CdTe/ZnS core/shell quantum dots (QDs) using tellurium dioxide (TeO2) as a tellurium precursor and thioglycolic acid (TGA) as stabilizer without any pre-treatment and inert atmosphere protection. As-synthesized QDs were characterized by transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), electron diffraction spectroscopy (EDS), X-ray powder diffraction (XRD), UV-vis and photoluminescence (PL). The spherical particles were uniformly distributed with the average diameters of 3.2 nm (CdTe QDs) and -5 nm (CdTe/ZnS QDs). By altering the reaction conditions, the emission wavelengths of the CdTe core QDs and CdTe/ZnS core/shell QDs could be tuned from 508 to 574 nm and 526 to 600 nm with narrow full widths at half maximum (FWHM) of 33 to 58 nm, respectively. Meanwhile, on the optimum condition, the luminescence efficiency of CdTe/ZnS QDs can achieve to 74%, which was higher than that of CdTe core QDs (24%).

One-pot aqueous synthesis of gadolinium doped CdTe quantum dots with dual imaging modalities

A facile one-pot strategy has been developed for the aqueous synthesis of Gd doped CdTe (Gd:CdTe) QDs as fluorescence and magnetic resonance imaging dual-modal agent. The prepared Gd:CdTe QDs showed narrow size distribution and the average size was less than 5nm. The amount of Gd3+ dopant in Gd:CdTe QDs significantly affected the optical properties of obtained QDs. The highest PL QY for the prepared Gd:CdTe QDs was up to 42.5%. The QDs showed the weak toxicity and significant enhancement in MRI signal. The specific relaxivity value (r1) was determined to be 4.22mM−1s−1. These properties make the prepared Gd:CdTe QDs be an effective dual-modal imaging agent and have great potential applications in biomedical field.

PH-Dependent Synthesis of Novel Structure-Controllable Polymer-Carbon NanoDots with High Acidophilic Luminescence and Super Carbon Dots Assembly for White Light-Emitting Diodes.

We use a pH-dependent solubility equilibrium to develop a one-pot aqueous synthesis of polymer carbon nanodots with novel structures. The chemical structure and photoluminescence (PL) were heavily influenced by the synthesis pH, with cross-linked polymer-carbon film (pH > 7), polymer carbon nanosheets (3 < pH < 7), and amorphous carbon structures (1 < pH < 3) achieved by altering the initial pH. Although pH-dependent structures frequently occur in typical semiconductors and supramolecular architectures involving metal, this is the first experimental work describing it in carbon nanodots. Supersmall carbon nanodots (SCNDs, ∼0.5 nm) were obtained at pH < 1; their direct white emission can be easily applied as an inexpensive color-changing layer in white LEDs. Investigation of the PL mechanism of the SCNDs revealed an uncommon multilevel highly emissive recombination channel, which could be possibly derived from the wide distributions of surface-state PL centers. Theoretical calculation of the single layer of the carbon dots further explored their band gap changes.

Facet effects of palladium nanocrystals for oxygen reduction in ionic liquids and for sensing applications.

Palladium nanocrystals enclosed by {100} and {110} crystal facets, were successfully synthesized through an aqueous one-pot synthesis method. A new thermal annealing approach was developed for fabricating these palladium nanocrystals as a working electrode on a gas permeable membrane to study the facet effects of the oxygen reduction process in an ionic liquid, 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ([Bmpy][NTf2]). Results were compared with the same processes at a conventional platinum electrode. Our study shows that the structural difference between the two facets of Pd nanocrystals has little effect on the oxygen reduction process but significantly affects the oxidation process of the superoxide. It is found that the Pd{110}/IL interface can better stabilize superoxide radicals revealed by a more positive oxidation potential compared to that of Pd{100}. In addition, the analytical characteristic of utilizing both palladium nanocrystals as electrodes for oxygen sensing is comparable with a polycrystal platinum oxygen sensor, in which Pd{110} presents the best sensitivity and lowest detection limit. Our results demonstrate the facet-dependence of oxygen reduction in an ionic liquid medium and provide the fundamental information needed to guide the applications of palladium nanocrystals in electrochemical gas sensor and fuel cell research.

Aqueous Synthesis of PEGylated Quantum Dots with Increased Colloidal Stability and Reduced Cytotoxicity.

Ligands used on the surface of colloidal nanoparticles (NPs) have a significant impact on physiochemical properties of NPs and their interaction in biological environments. In this study, we report a one-pot aqueous synthesis of 3-mercaptopropionic acid (MPA)-functionalized CdTe/CdS/ZnS quantum dots (Qdots) in the presence of thiol-terminated methoxy polyethylene glycol (mPEG) molecules as a surface coordinating ligand. The resulting mPEG-Qdots were characterized by using ζ potential, FTIR, thermogravimetric (TG) analysis, and microscale thermophoresis (MST) studies. We investigated the effect of mPEG molecules and their grafting density on the Qdots photophysical properties, colloidal stability, protein binding affinity, and in vitro cellular toxicity. Moreover, cellular binding features of the resulting Qdots were examined by using three-dimensional (3D) tumor-like spheroids, and the results were discussed in detail. Promisingly, mPEG ligands were found to increase colloidal stability of Qdots, reduce adsorption of proteins to the Qdot surface, and mitigate Qdot-induced side effects to a great extent. Flow cytometry and confocal microscopy studies revealed that PEGylated Qdots exhibited distinctive cellular interactions with respect to their mPEG grafting density. As a result, mPEG molecules demonstrated a minimal effect on the ZnS shell deposition and the Qdot fluorescence efficiency at a low mPEG density, whereas they showed pronounced effect on Qdot colloidal stability, protein binding affinity, cytotoxicity, and nonspecific binding at a higher mPEG grafting amount.

One-pot aqueous synthesis of germanium-doped cadmium sulfide quantum dots as fluorescent probes for cell imaging

Water-soluble germanium-doped cadmium sulfide quantum dots (Ge:CdS q-dots) were successfully synthesized by a facile one-pot method, and used as fluorescent probes for labeling live MCF-7 cells. The optical properties of the q-dots and several key parameters of the synthesis conditions were studied, and the mechanism of these parameters was also discussed. After doping with germanium, the PL intensity increased 50%, while improving the photostability and fluorescence quantum yield. Furthermore, the toxicity of CdS quantum dot decreased after doping with germanium due to its low toxicity, which greatly improved the CdS quantum dots biocompatibility. Then the doped quantum dots modified with folic acid (FA) to use as fluorescent probes, which expanded the application of semiconductor quantum dots in the biomedical field.

Polyoxometalate-mediated one-pot synthesis of Pd nanocrystals with controlled morphologies for efficient chemical and electrochemical catalysis.

Polyoxometalates (POMs), as inorganic ligands, can endow metal nanocrystals (NCs) with unique reactivities on account of their characteristic redox properties. In the present work, we present a facile POM-mediated one-pot aqueous synthesis method for the production of single-crystalline Pd NCs with controlled shapes and sizes. The POMs could function as both reducing and stabilizing agents in the formation of NCs, and thus gave a fine control over the nucleation and growth kinetics of NCs. The prepared POM-stabilized Pd NCs exhibited excellent catalytic activity and stability for electrocatalytic (formic acid oxidation) and catalytic (Suzuki coupling) reactions compared to Pd NCs prepared without the POMs. This shows that the POMs play a pivotal role in determining the catalytic performance, as well as the growth, of NCs. We envision that the present approach can offer a convenient way to develop efficient NC-based catalyst systems.