Magnetic hybrid materials in liquid crystals

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Martin Hähsler ◽  
Ingo Appel ◽  
Silke Behrens
Keyword(s):  
Liquid Crystals ◽  
Magnetic Nanoparticles ◽  
Hybrid Materials ◽  
Hybrid Material ◽  
Colloidal Stability ◽  
General Introduction ◽  
Preparation Methods ◽  
Semiconducting Properties ◽  
Dendritic Structures

AbstractThe integration of nanoparticles with magnetic, ferroelectric or semiconducting properties into liquid crystals (LCs) has attracted great interest both for fundamental investigations and for technological applications. Here, an overview of hybrid materials based on magnetic nanoparticles (MNPs) and thermotropic LCs is given. After a general introduction to thermotropic LCs and LC-MNP hybrid materials, various preparation methods established by us are presented. The synthesis of shape-(an)isotropic MNPs, their functionalization by tailored (pro)mesogenic ligands with linear or dendritic structures and their integration into LC hosts are discussed. The characterization of the MNPs, (pro)mesogenic ligands and resulting MNP-LC hybrid materials is described to show the influence of MNP functionalization on the MNP-LC interactions including aspects such as colloidal stability and structuring in the LC host. Overall, we show that the physical properties of the hybrid material are significantly influenced not only by the MNPs (i.e., their size, shape and composition) but also by their surface properties (i.e., the structure of the (pro)mesogenic ligands).

Pseudopolyrotaxane Structure Constructed by Polycaprolactone (PCL) Grafted on Multi-Walled Carbon Nanotubes and α-Cyclodextrins

2012 ◽  
Vol 487 ◽  
pp. 668-671 ◽  
Author(s):  
Shuai Hu ◽  
Mi Zhou ◽  
Song Hua Kong ◽  
Xin Qian
Keyword(s):  
Carbon Nanotubes ◽  
Supramolecular Chemistry ◽  
Hybrid Materials ◽  
Hybrid Material ◽  
New Approach ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes

Abstract The multi-walled carbon nanotubes (MWNTs) are modified through acidification, followed by the graft of polycaprolactone. The supramolecular forces of α-cyclodextrins (α-CDs) and PCL are used to produce MWNTs hybrid materials with pseudopolyrotaxane structure. XRD, FTIR, TGA, DSC are used for the characterization of its product. The preparation of this hybrid material provides a new approach for modifying carbon nanotubes in supramolecular chemistry with the expectation of applying this hybrid materials to the field of biomedicine.

Magnetorelaxometry procedures for quantitative imaging and characterization of magnetic nanoparticles in biomedical applications

2015 ◽  
Vol 60 (5) ◽  
Author(s):  
Maik Liebl ◽  
Frank Wiekhorst ◽  
Dietmar Eberbeck ◽  
Patricia Radon ◽  
Dirk Gutkelch ◽  
...  
Keyword(s):  
Magnetic Nanoparticles ◽  
Biomedical Applications ◽  
Colloidal Stability ◽  
Quantitative Imaging ◽  
Local Environment ◽  
Quantitative Information ◽  
Magnetic Drug Targeting ◽  
Spatially Resolved ◽  
Fast Change

AbstractQuantitative knowledge about the spatial distribution and local environment of magnetic nanoparticles (MNPs) inside an organism is essential for guidance and improvement of biomedical applications such as magnetic hyperthermia and magnetic drug targeting. Magnetorelaxometry (MRX) provides such quantitative information by detecting the magnetic response of MNPs following a fast change in the applied magnetic field.In this article, we review our MRX based procedures that enable both the characterization and the quantitative imaging of MNPs in a biomedical environment.MRX characterization supported the selection of an MNP system with colloidal stability and suitable cellular MNP uptake. Spatially resolved MRX, a procedure employing multi-channel MRX measurements allowed forThese MRX based measurement and analysis procedures have substantially supported the development of MNP based biomedical applications.

Hydrogel-clay Nanocomposites as Carriers for Controlled Release

2020 ◽  
Vol 27 (6) ◽  
pp. 919-954 ◽  
Author(s):  
Raluca Ianchis ◽  
Claudia Mihaela Ninciuleanu ◽  
Ioana Catalina Gifu ◽  
Elvira Alexandrescu ◽  
Cristina Lavinia Nistor ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Controlled Release ◽  
Hybrid Materials ◽  
Pharmaceutical Formulations ◽  
Tree Of Life ◽  
Present Review ◽  
Clay Nanocomposites ◽  
Delivery Platform ◽  
Complex Hybrid

The present review aims to summarize the research efforts undertaken in the last few years in the development and testing of hydrogel-clay nanocomposites proposed as carriers for controlled release of diverse drugs. Their advantages, disadvantages and different compositions of polymers/biopolymers with diverse types of clays, as well as their interactions are discussed. Illustrative examples of studies regarding hydrogel-clay nanocomposites are detailed in order to underline the progressive researches on hydrogel-clay-drug pharmaceutical formulations able to respond to a series of demands for the most diverse applications. Brief descriptions of the different techniques used for the characterization of the obtained complex hybrid materials such as: swelling, TGA, DSC, FTIR, XRD, mechanical, SEM, TEM and biology tests, are also included. Enlightened by the presented data, we can suppose that hydrogel-clay nanocomposites will still be a challenging subject of global assiduous researches. We can dare to dream to an efficient drug delivery platform for the treatment of multiple affection concomitantly, these being undoubtedly like ”a tree of life” bearing different kinds of fruits and leaves proper for human healing.

scholarly journals Adsorption Studies on Magnetic Nanoparticles Functionalized with Silver to Remove Nitrates from Waters

Water ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 1757
Author(s):  
Yesica Vicente-Martínez ◽  
Manuel Caravaca ◽  
Antonio Soto-Meca ◽  
Miguel Ángel Martín-Pereira ◽  
María del Carmen García-Onsurbe
Keyword(s):  
Magnetic Nanoparticles ◽  
Nitrate Content ◽  
Adsorption Efficiency ◽  
Experimental Conditions ◽  
Dependent Behavior ◽  
Before And After ◽  
Naoh Solution ◽  
High Concentrations ◽  
Interference Studies

This paper presents a novel procedure for the treatment of contaminated water with high concentrations of nitrates, which are considered as one of the main causes of the eutrophication phenomena. For this purpose, magnetic nanoparticles functionalized with silver (Fe3O4@AgNPs) were synthesized and used as an adsorbent of nitrates. Experimental conditions, including the pH, adsorbent and adsorbate dose, temperature and contact time, were analyzed to obtain the highest adsorption efficiency for different concentration of nitrates in water. A maximum removal efficiency of 100% was reached for 2, 5, 10 and 50 mg/L of nitrate at pH = 5, room temperature, and 50, 100, 250 and 500 µL of Fe3O4@AgNPs, respectively. The characterization of the adsorbent, before and after adsorption, was performed by energy dispersive X-ray spectroscopy, scanning electron microscopy, Brunauer-Emmett-Teller analysis and Fourier-transform infrared spectroscopy. Nitrates can be desorbed, and the adsorbent can be reused using 500 µL of NaOH solution 0.01 M, remaining unchanged for the first three cycles, and exhibiting 90% adsorption efficiency after three regenerations. A deep study on equilibrium isotherms reveals a pH-dependent behavior, characterized by Langmuir and Freundlich models at pH = 5 and pH = 1, respectively. Thermodynamic studies were consistent with physicochemical adsorption for all experiments but showed a change from endothermic to exothermic behavior as the temperature increases. Interference studies of other ions commonly present in water were carried out, enabling this procedure as very selective for nitrate ions. In addition, the method was applied to real samples of seawater, showing its ability to eliminate the total nitrate content in eutrophized waters.

scholarly journals Production and characterization of chitooligosaccharides by the fungal chitinase Chit42 immobilized on magnetic nanoparticles and chitosan beads: selectivity, specificity and improved operational utility

RSC Advances ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 5529-5536
Author(s):  
Peter E. Kidibule ◽  
Jessica Costa ◽  
Andrea Atrei ◽  
Francisco J. Plou ◽  
Maria Fernandez-Lobato ◽  
...  
Keyword(s):  
Magnetic Nanoparticles ◽  
Industrial Application ◽  
Chitosan Beads

Chitin-active enzymes are of great biotechnological interest due to the wide industrial application of chitinolytic materials.

scholarly journals Synthesis and Characterization of Novel Bio-Chiral Dopants Obtained from Bio-Betulin Produced by a Fermentation Process

Crystals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 785
Author(s):  
Veridiana G. Guimarães ◽  
Anastasiia Svanidze ◽  
Tianyi Guo ◽  
Pawan Nepal ◽  
Robert J. Twieg ◽  
...  
Keyword(s):  
Liquid Crystals ◽  
Natural Product ◽  
Fermentation Process ◽  
Synthesis And Characterization ◽  
Cholesteric Liquid Crystals ◽  
And Performance ◽  
Chiral Dopants

Cholesteric liquid crystals are frequently produced by the addition of chiral dopants to achiral nematic hosts. We report here the synthesis and performance of chiral dopants obtained from bio-betulin produced by a fermentation process. An important aspect of this work is to point out that the fermentation process used to obtain the starting materials is much easier and cheaper when carried out in large volumes than isolating it from the natural product. The performance of the dopants obtained from bio-betulin is indistinguishable from those obtained from commercially available synthetic betulin.

scholarly journals Hybrid material by anchoring a ruthenium(ii) imine complex to SiO2: preparation, characterization and DFT studies

RSC Advances ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 6221-6233
Author(s):  
G. Eliad Benitez-Medina ◽  
Raúl Flores ◽  
Luis Vargas ◽  
Fernando Cuenú ◽  
Pankaj Sharma ◽  
...  
Keyword(s):  
Hybrid Materials ◽  
Hybrid Material ◽  
Dft Studies ◽  
Ft Ir ◽  
Silica Hybrid

Ruthenium–silica hybrid materials were synthesized. The process was tracked by FT-IR, DRS-UV-Vis, DFT and deconvolution analyses, finding experimental–theoretical correlation.

Curcuminoids-conjugatiked multicore magnetic nanoparticles: design and characterization of a potential theranostic nanoplatform

2021 ◽  
pp. 160448
Author(s):  
Evelyn C.S. Santos ◽  
Jamili A. Cunha ◽  
Marcel G. Martins ◽  
Bianca M. Galeano-Villar ◽  
Richard J. Caraballo-Vivas ◽  
...  
Keyword(s):  
Magnetic Nanoparticles

scholarly journals Phthalocyanine-Functionalized Magnetic Silica Nanoparticles as Anion Chemosensors

Sensors ◽  
2021 ◽  
Vol 21 (5) ◽  
pp. 1632
Author(s):  
João M. M. Rodrigues ◽  
Andreia S. F. Farinha ◽  
Zhi Lin ◽  
José A. S. Cavaleiro ◽  
Augusto C. Tome ◽  
...  
Keyword(s):  
Magnetic Nanoparticles ◽  
Dimethyl Sulfoxide ◽  
Silica Nanoparticles ◽  
Hybrid Material ◽  
Limit Of Detection ◽  
Active Material ◽  
Anion Detection ◽  
Anionic Species ◽  
Magnetic Silica ◽  
Magnetic Silica Nanoparticles

Anionic species are one of the most common pollutants in residual and freshwaters. The presence of anthropogenic anions in water drastically increases the toxicity to living beings. Here, we report the preparation of a new optical active material based on tri(tosylamino)phthalocyanines grafted to ferromagnetic silica nanoparticles for anion detection and removal. The new unsymmetrical phthalocyanines (Pcs) proved to be excellent chemosensors for several anions (AcO−, Br−, Cl−, CN−, F−, H2PO4−, HSO4−, NO2−, NO3−, and OH−) in dimethyl sulfoxide (DMSO). Furthermore, the Pcs were grafted onto magnetic nanoparticles. The resulting novel hybrid material showed selectivity and sensitivity towards CN−, F−, and OH− anions in DMSO with limit of detection (LoD) of ≈4.0 µM. In water, the new hybrid chemosensor demonstrated selectivity and sensitivity for CN− and OH− anions with LoD of ≈0.2 µM. The new hybrids are easily recovered using a magnet, allowing recyclability and reusability, after acidic treatment, without losing the sensing proprieties.

Sign in / Sign up

Export Citation Format

Share Document