scholarly journals Stimuli-responsive HBPS-g-PDMAEMA and its application as nanocarrier in loading hydrophobic molecules

2016 ◽  
Vol 12 ◽  
pp. 939-949 ◽  
Author(s):  
Yongsheng Chen ◽  
Li Wang ◽  
Haojie Yu ◽  
Zain-Ul-Abdin ◽  
Ruoli Sun ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Ph Value ◽  
Polymer Concentration ◽  
Nile Red ◽  
Stimuli Responsive ◽  
Guest Molecules ◽  
Drug Controlled Release ◽  
H Nmr ◽  
Vis Spectroscopy ◽  
Small Hydrophobic

The topic of stimuli-responsive nanocarriers for loading guest molecules is dynamic. It has been widely studied in applications including drug controlled release, smart sensing, catalysis, and modeling. In this paper, a graft copolymer (hyperbranched polystyrene)-g-poly[2-(dimethylamino)ethyl methacrylate] (HBPS-g-PDMAEMA) was synthesized and characterized by 1H NMR and GPC. It was observed that the star-like HBPS-g-PDMAEMA formed aggregates in aqueous solution. The influence of polymer concentration, ionic strength and pH value on the aggregates in aqueous solution was investigated by using UV–vis spectroscopy and DLS analysis. The results showed that size of aggregates was affected by a corresponding stimulus. In addition, the loading ability of HBPS-g-PDMAEMA aggregates was investigated by using pyrene or Nile red as the model guest molecules by using UV–vis and fluorescence spectroscopy. The results showed that HBPS-g-PDMAEMA aggregates were capable to encapsulate small hydrophobic molecules. These newly prepared HBPS-g-PDMAEMA nanocarriers might be used in, e.g., medicine or catalysis.

Effect of Concentration on the Ionic Interaction between Polystyrene Sulfonate and Cationic Surfactant in Aqueous Solution

2018 ◽  
Vol 916 ◽  
pp. 24-29
Author(s):  
Agus Haryono ◽  
Muhammad Ghozali ◽  
Sri Budi Harmami ◽  
Yenny Meliana
Keyword(s):  
Aqueous Solution ◽  
Nmr Spectra ◽  
Polymer Concentration ◽  
Polystyrene Sulfonate ◽  
Ionic Interaction ◽  
Anionic Polymer ◽  
H Nmr ◽  
Sulfonation Degree ◽  
Polystyrene Waste

Polystyrene sulfonate (PSS) were prepared by sulfonation method of polystyrene using sulfuric acid. Abundant amount of polystyrene waste can be reused as a coagulant, membrane for polymer fuel cell and anionic-cationic polymer interactions. The characterization of PSS was carried out by using UV-Vis, Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR) spectra, molecular weight and analysis of sulfonation degree. The degree of sulfonation was obtained at 94,18%. Ionic interaction between anionic polymer PSS and cetyltrimethylammonium bromide (CTAB) as cationic compound in aqueous solution were analyzed by using dynamic light scattering (DLS), conductometry and fluorimetry. Behavior of conductivity have been calculated the critical micelle concentration (cmc). The FTIR and 1H-NMR spectra showed the ionic interaction between PSS and CTAB. This ionic interaction can be controlled by changing the polymer concentration.

Dual stimuli-responsive nano-structure transition of three-arm branched amphiphilic polymers containing ferrocene (Fc) and azobenzene (Azo) moieties in aqueous solution

Soft Matter ◽  
2019 ◽  
Vol 15 (43) ◽  
pp. 8855-8864
Author(s):  
Zhukang Du ◽  
Xiaolong Yan ◽  
Ning Sun ◽  
Biye Ren
Keyword(s):  
Aqueous Solution ◽  
Molecular Weight ◽  
Polymer Concentration ◽  
Amphiphilic Polymers ◽  
Stimuli Responsive ◽  
Nano Structure ◽  
Structure Transition

Amphiphilic polymers can self-assemble into various nanostructures, depending on the PEO molecular weight, applied stimuli, and polymer concentration.

Structural study of the novel deuterated calix[4]pyrrole complex d 12-meso-tetrakis(4-methoxyphenyl)-meso-tetramethylcalix[4]pyrrole–pyridine N-oxide–acetonitrile (1/1/1)

2017 ◽  
Vol 73 (3) ◽  
pp. 254-258
Author(s):  
Ying-Chun He ◽  
Ji-Gang Pan ◽  
Dian-Sheng Liu
Keyword(s):  
Single Crystal ◽  
Hydrophobic Interactions ◽  
The Novel ◽  
Guest Molecules ◽  
Cone Conformation ◽  
X Ray ◽  
Molecular Binding ◽  
H Nmr ◽  
Vis Spectroscopy ◽  
D 12

Calix[4]pyrroles act as powerful receptors for electron-rich neutral guests and anionic guests in organic solvents. For the electron-rich neutral guest pyridine N-oxide, calix[4]pyrrole, with a deep cavity, provides an appropriate environment. The ability of calix[4]pyrrole to host binding guest molecules is the result of hydrogen bonding, π–π, C—H...π and hydrophobic interactions of the cavity. The novel title complex, C52H40D12N4O4·C5H5NO·C2H3N, based on d 12-meso-tetrakis(4-methoxyphenyl)-meso-tetramethylcalix[4]pyrrole, has been assembled using an excess of pyridine N-oxide and is the first deuterated complex of calix[4]pyrrole. A single-crystal X-ray study shows that the receptor adopts a cone conformation with the N-oxide fragment encapsulated deep within the cavity. 1H NMR spectroscopy was used to probe the molecular binding formation in CD3CN. The results are consistent with the single-crystal X-ray study in identifying that the pyridine N-oxide molecule occupies the cavity of the calix[4]pyrrole molecule. UV–vis spectroscopy revealed that the calix[4]pyrrole receptor molecules are able to form 1:1 inclusion complexes in CH3CN.

scholarly journals AQUEOUS SOLUTIONS OF CHITOSAN: VISCOMETRIC AND FLOCCULATION PROPERTIES

2021 ◽  
Vol 2021 ◽  
pp. 123-130
Author(s):  
C.-E. Brunchi ◽  
L. Ghimici
Keyword(s):  
Experimental Data ◽  
Aqueous Solution ◽  
Zeta Potential ◽  
Aqueous Solutions ◽  
Room Temperature ◽  
Polymer Concentration ◽  
Pyrethroid Insecticides ◽  
Vis Spectroscopy ◽  
Insecticide Concentration ◽  
Maximum Removal

The hydrodynamic and flocculation properties of aqueous solution of chitosan (CS) were investigated at room temperature. The viscometric data of dilute CS solutions were discussed in terms of Wolf method as a function of polymer concentration, salt nature (NaCl, NaNO3, and CaCl2) and concentration. The flocculation properties in emulsions of some commercial pyrethroid insecticides (Fastac 10 EC (F), Decis (Dc) and Karate Zeon (KZ)) were evaluated. The viscosity measurements reveal that the experimental data fit well with the Wolf model and the [η] values decrease in salt aqueous solutions. For the same insecticide concentration (0.02%, v/v), UV-Vis spectroscopy measurements show maximum removal efficiency around 90% for Fastac 10EC and Decis and 80% for Karate Zeon. The residual KZ absorbance decreased with the increase of insecticide concentration in the initial emulsion, from 80% for the lowest concentration (0.02%, v/v) to around 90% for the highest one (0.06%, v/v). The supernatant zeta potential dependence on the chitosan dose pleads for the charge neutralization as the main mechanism for the flocculation of pyrethroid insecticide particles.

Enantioselective Recognition of Chiral Guests by the Water-Soluble Chiral Keplerate {Mo132} Spherical Capsule with 30 Inner Lactate Ligands

2019 ◽  
Author(s):  
Nancy Watfa ◽  
Weimin Xuan ◽  
Zoe Sinclair ◽  
Robert Pow ◽  
Yousef Abul-Haija ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Chiral Recognition ◽  
Association Constants ◽  
Water Soluble ◽  
Enantioselective Recognition ◽  
H Nmr ◽  
Dosy Nmr ◽  
Spherical Capsule ◽  
Surface Pores ◽  
Guest Chemistry

Investigations of chiral host guest chemistry are important to explore recognition in confined environments. Here, by synthesizing water-soluble chiral porous nanocapsule based on the inorganic metal-oxo Keplerate-type cluster, {Mo<sub>132</sub>} with chiral lactate ligands with the composition [Mo<sub>132</sub>O<sub>372</sub>(H<sub>2</sub>O)<sub>72</sub>(<i>x-</i>Lactate)<sub>30</sub>]<sup>42-</sup> (<i>x</i> = D or L), it was possible to study the interaction with a chiral guest, L/D-carnitine and (<i>R</i>/<i>S</i>)-2-butanol in aqueous solution. The enantioselective recognition was studied by quantitative <sup>1</sup>H NMR and <sup>1</sup>H DOSY NMR which highlighted that the chiral recognition is regulated by two distinct sites. Differences in the association constants (K) of L- and D-carnitine, which, due to their charge, are generally restricted from entering the interior of the host, are observed, indicating that their recognition predominantly occurs at the surface pores of the structure. Conversely, a larger difference in association constants (K<i><sub>S</sub></i>/K<i><sub>R</sub></i> = 3) is observed for recognition within the capsule interior of (<i>R</i>)- and (<i>S</i>)-2-butanol.

Exploring the characteristics of the nickel oxide nanoparticles via Sol - gel method

2020 ◽  
Vol 3 (3) ◽  
Author(s):  
Jothi M ◽  
Sowmiya K
Keyword(s):  
Nickel Oxide ◽  
Ph Value ◽  
Lattice Structure ◽  
Sol Gel ◽  
Systematic Change ◽  
Average Crystalline Size ◽  
Nio Nanoparticles ◽  
Nickel Oxide Nanoparticles ◽  
X Ray ◽  
Vis Spectroscopy

Nickel Oxide (NiO) is an important transition metal oxide with cubic lattice structure. NiO is thermally stable that is suitable for tremendous applications in the field of optic, ceramic,glass, electro-chromic coatings, plastics, textiles, nanowires, nanofibers, electronics,energy technology, bio-medicine, magnetism and so on. In this present study, NiO nanoparticles were successfully synthesized by sol-gel technique. Nano-sols were prepared by dissolving Nickel-Chloride [NiCl2.6H2O] in NaOH solvent and were converted into nano structured gel on precipitation. A systematic change in preparation parameters like calcination temperature, time, pH value has been noticed in order to predict the influence on crystallite size. Then the prepared samples were characterized by the X-ray Diffraction Spectroscopic (XRD), UV-VIS Spectroscopy, Fourier Transform Infra-Red Spectroscopy (FTIR), Energy Dispersive X-ray Spectroscopy (EDX), Scanning Electron Microscopy (SEM) and Particle Size Analyzer (PSA). From XRD, the average crystalline-size has been calculated by Debye-Scherrer Equation and it was found to be 12.17 nm and the band gap energy of Nickel oxide (NiO) from UV studies reveals around 3.85 eV. Further, EDX and FTIR studies, confirm the presences of NiO nanoparticles. The SEM study exhibits the spherical like morphology of Nickel oxide (NiO). Further from PSA, the mean value of NiO nanoparticles has been determined.

scholarly journals Selenium in wastewater can be adsorbed by modified natural zeolite and reused in vegetable growth

2021 ◽  
Vol 104 (2) ◽  
pp. 003685042110198
Author(s):  
Xiao Zhang ◽  
Xinyuan Li ◽  
Zihao Jin ◽  
Sadam Hussain Tumrani ◽  
Xiaodong Ji
Keyword(s):  
Aqueous Solution ◽  
Ph Value ◽  
Soil Improvement ◽  
Pollutant Removal ◽  
Maximum Adsorption Capacity ◽  
Selenium Content ◽  
Water Release ◽  
Soil Release ◽  
Release Ratio ◽  
Water Pollutant

Modified natural zeolites (MNZ) are widely used in pollutant removal, but how to address these MNZ that have adsorbed pollutants must be considered. Selenium is an essential trace element for metabolism and is also a water pollutant. Selenium is adsorbed in the water by MNZ in this study first. Then the Brassica chinensis L. was planted in the soil which contains the MNZ loaded with selenium (MNZ-Se) to explore selenium uptake. MNZ-Se release tests in water and soil were also considered. The results showed the following: (1) The maximum adsorption capacity of MNZ for selenium is 46.90 mg/g. (2) Water release experiments of MNZ-Se showed that regardless of how the pH of the aqueous solution changes, the trend of the release of selenium from MNZ-Se in aqueous solution is not affected and first decreases before stabilizing. (3) Soil release experiments of MNZ-Se showed that the selenium content in the soil increased and reached the concentration in the standard of selenium-rich soil. Addition amount and soil pH value will affect the release ratio. The release ratio of MNZ-Se in the water was higher than that in the soil. (4) With an increase in the soil MNZ-Se content, the selenium content in the soil and B. c increases. Above all, MZN can be a good medium for water pollutant removal and soil improvement.

Stimuli-Responsive Supramolecular Chirality Switching and Nanoassembly Constructed by n-Shaped Amphiphilic Molecules in Aqueous Solution

Langmuir ◽  
2021 ◽  
Vol 37 (3) ◽  
pp. 1215-1224
Author(s):  
Yuntian Yang ◽  
Qingqing Han ◽  
Yi-rong Pei ◽  
Shengsheng Yu ◽  
Zhegang Huang ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Stimuli Responsive ◽  
Supramolecular Chirality ◽  
Amphiphilic Molecules

scholarly journals Removal of Phenol from Aqueous Solution Using Internal Microelectrolysis with Fe-Cu: Optimization and Application on Real Coking Wastewater

Processes ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 720
Author(s):  
Do Tra Huong ◽  
Nguyen Van Tu ◽  
Duong Thi Tu Anh ◽  
Nguyen Anh Tien ◽  
Tran Thi Kim Ngan ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Ph Value ◽  
Reaction Rate Constant ◽  
Phenol Concentration ◽  
Treated Wastewater ◽  
Coking Wastewater ◽  
X Ray ◽  
Chemical Plating ◽  
Internal Electrolysis ◽  
Phenol Decomposition

Fe-Cu materials were synthesized using the chemical plating method from Fe powder and CuSO4 5% solution and then characterized for surface morphology, composition and structure by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD), respectively. The as-synthesized Fe-Cu material was used for removal of phenol from aqueous solution by internal microelectrolysis. The internal electrolysis-induced phenol decomposition was then studied with respect to various parameters such as pH, time, Fe-Cu material weight, phenol concentration and shaking speed. The optimal phenol decomposition (92.7%) was achieved under the conditions of (1) a pH value of phenol solution of 3, (2) 12 h of shaking at the speed of 200 rpm, (3) Fe-Cu material weight of 10 g/L, (4) initial phenol concentration of 100.98 mg/L and (5) at room temperature (25 ± 0.5 °C). The degradation of phenol using Fe-Cu materials obeyed the second-order apparent kinetics equation with a reaction rate constant of k of 0.009 h−1L mg−1. The optimal process was then tested against real coking wastewater samples, resulting in treated wastewater with favorable water indicators. Current findings justify the use of Fe-Cu materials in practical internal electrolysis processes.

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