Antibody conjugated PLGA nanocarriers and superparmagnetic nanoparticles for targeted delivery of oxaliplatin to cells from colorectal carcinoma

Anti-CD133 monoclonal antibody (Ab)-conjugated poly(lactide-co-glycolide) (PLGA) nanocarriers, for the targeted delivery of oxaliplatin (OXA) and superparamagnetic nanoparticles (IO-OA) to colorectal cancer cells (CaCo-2), were designed, synthesized, characterized, and evaluated in this study. The co-encapsulation of OXA and IO-OA was achieved in two types of polymeric carriers, namely, PLGA and poly(lactide-co-glycolide)-poly(ethylene glycol) (PLGA-PEG) by double emulsion. PLGA_IO-OA_OXA and PEGylated PLGA_IO-OA_OXA nanoparticles displayed a comparable mean diameter of 207 ± 70 nm and 185 ± 119 nm, respectively. The concentration of the released OXA from the PEGylated PLGA_IO-OA_OXA increased very rapidly, reaching ~100% release after only 2 h, while the PLGA_IO-OA_OXA displayed a slower and sustained drug release. Therefore, for a controlled OXA release, non-PEGylated PLGA nanoparticles were more convenient. Interestingly, preservation of the superparamagnetic behavior of the IO-OA, without magnetic hysteresis all along the dissolution process, was observed. The non-PEGylated nanoparticles (PLGA_OXA, PLGA_IO-OA_OXA) were selected for the anti-CD133 Ab conjugation. The affinity of Ab-coated nanoparticles for CD133-positive cells was examined using fluorescence microscopy in CaCo-2 cells, which was followed by a viability assay. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.Grantová Agentura České Republiky, GA ČR: 19-02889S, A2_FCHI_2021_01

Ferrofluid for radiofrequency capacitive hyperthermia: In-vitro study

The current work deals with preparation and characterization of electrically lossy ferrofluid which can be used as a mediator for radio frequency (RF) - capacitive hyperthermia method. To this end, ferrofluid that can absorb the energy of alternating electrical field at the frequencies commonly employed in RF-capacitive hyperthermia (13.56 and 27.12 MHz) has been prepared by co-precipitation method. This ferrofluid comprises of electrically conductive component with core-shell structure, i.e. magnetite nanoparticles (NPs) coated by dextran, organized in chain-like structure. The effect of RF - capacitive hyperthermia in the presence of mediator was studied on the series of tests performed on HaCaT and HepG2 cell lines using MMT test. The RF-electrical field (13.56 MHz) with controllable power output was applied using the EHY-110 SA (Oncotherm group) to increase the temperature of samples from 37°C up to target temperature of 44°C. The results of in-vitro test clearly indicate that the usage of capacitive heating of obtained ferrofluid substantially contribute to cytotoxic effect of hyperthermia treatment.Ministry of Education, Youth and Sports of the Czech Republic Program NPU I [LO1504

Sonochemical synthesis of Gd3+ doped CoFe2O4 spinel ferrite nanoparticles and its physical properties

In this work, a facile and green method for gadolinium doped cobalt ferrite (CoFe2−xGdxO4; x = 0.00, 0.05, 0.10, 0.15, 0.20) nanoparticles by using ultrasonic irradiation was reported. The impact of Gd3+ substitution on the structural, magnetic, dielectric and electrical properties of cobalt ferrite nanoparticles was evaluated. The sonochemically synthesized spinel ferrite nanoparticles were characterized by X-ray Diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), vibrating sample magnetometer (VSM). X-ray diffraction (XRD) study confirmed the formation of single phase spinel ferrite of CoFe2−xGdxO4 nanoparticles. XRD results also revealed that ultrasonic irradiation seems to be favourable to achieve highly crystalline single crystal phase gadolinium doped cobalt ferrite nanoparticles without any post annealing process. Fourier Transform Infrared and Raman Spectra confirmed the formation of spinel ferrite crystal structure. X-ray photoelectron spectroscopy revealed the impact of Gd3+ substitution in CoFe2O4 nanoparticles on cation distribution at the tetrahedral and octahedral site in spinel ferrite crystal system. The electrical properties showed that the Gd3+ doped cobalt ferrite (CoFe2−xGdxO4; x = 0.20) exhibit enhanced dielectric constant (277 at 100 Hz) and ac conductivity (20.2 × 10−9 S/cm at 100 Hz). The modulus spectroscopy demonstrated the impact of Gd3+ substitution in cobalt ferrite nanoparticles on grain boundary relaxation time, capacitance and resistance. Magnetic property measurement revealed that the coercivity decreases with Gd3+ substitution from 234.32 Oe (x = 0.00) to 12.60 Oe (x = 0.05) and further increases from 12.60 Oe (x = 0.05) to 68.62 Oe (x = 0.20). Moreover, saturation magnetization decreases with Gd3+ substitution from 40.19 emu/g (x = 0.00) to 21.58 emu/g (x = 0.20). This work demonstrates that the grain size and cation distribution in Gd3+ doped cobalt ferrite nanoparticles synthesized by sonochemical method, is effective in controlling the structural, magnetic, and electrical properties, and can be find very promising applications. © 2017 Elsevier B.V.Ministry of Education, Youth and Sports of the Czech Republic - Program NPU I [LO1504

Magnetic nanomaterials for arterial embolization and hyperthermia of parenchymal organs tumors: A review

Magnetic hyperthermia (MH), proposed by R. K. Gilchrist in the middle of the last century as local hyperthermia, has nowadays become a recognized method for minimally invasive treatment of oncological diseases in combination with chemotherapy (ChT) and radiotherapy (RT). One type of MH is arterial embolization hyperthermia (AEH), intended for the presurgical treatment of primary inoperable and metastasized solid tumors of parenchymal organs. This method is based on hyperthermia after transcatheter arterial embolization of the tumor's vascular system with a mixture of magnetic particles and embolic agents. An important advantage of AEH lies in the double effect of embolotherapy, which blocks blood flow in the tumor, and MH, which eradicates cancer cells. Consequently, only the tumor undergoes thermal destruction. This review introduces the progress in the development of polymeric magnetic materials for application in AEH. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.8X20041; Ministerstvo Školství, Mládeže a Tělovýchovy, MŠMT: RP/CPC/2020/00

Polypropylene nanocomposite filled with spinel ferrite NiFe 2 O 4 nanoparticles and in-situ thermally-reduced graphene oxide for electromagnetic interference shielding application

Herein, we presented electromagnetic interference shielding characteristics of NiFe2O4 nanoparticles-in-situ thermally-reduced graphene oxide (RGO)-polypropylene nanocomposites with the variation of reduced graphene oxide content. The structural, morphological, magnetic, and electromagnetic parameters and mechanical characteristics of fabricated nanocomposites were investigated and studied in detail. The controllable composition of NiFe 2 O 4 -RGO-Polypropylene nanocomposites exhibited electromagnetic interference (EMI) shielding effectiveness (SE) with a value of 29.4 dB at a thickness of 2 mm. The enhanced EMI shielding properties of nanocomposites with the increase of RGO content could be assigned to enhanced attenuation ability, high conductivity, dipole and interfacial polarization, eddy current loss, and natural resonance. The fabricated lightweight NiFe 2 O 4 -RGO-Polypropylene nanocomposites have potential as a high performance electromagnetic interference shielding nanocomposite. © 2019 by the authors. Licensee MDPI, Basel, Switzerland.Ministry of Education, Youth and Sports of the Czech Republic-Program NPU I [LO1504, IGA/CPS/2019/007]; Tomas Bata University in Zlin, Czech Republi

CuxCo1-xFe2O4 (x = 0.33, 0.67, 1) Spinel Ferrite Nanoparticles Based Thermoplastic Polyurethane Nanocomposites with Reduced Graphene Oxide for Highly Efficient Electromagnetic Interference Shielding

CuxCo1-x Fe2O4 (x = 0.33,0.67,1)-reduced graphene oxide (rGO)-thermoplastic polyurethane (TPU) nanocomposites exhibiting highly efficient electromagnetic interference (EMI) shielding were prepared by a melt-mixing approach using a microcompounder. Spinel ferrite Cu0.33Co0.67Fe2O4 (Cu-CoF1), Cu0.67Co0.33Fe2O4 (CuCoF2) and CuFe2O4 (CuF3) nanoparticles were synthesized using the sonochemical method. The CuCoF1 and CuCoF2 exhibited typical ferromagnetic features, whereas CuF3 displayed superparamagnetic characteristics. The maximum value of EMI total shielding effectiveness (SEt) was noticed to be 42.9 dB, 46.2 dB, and 58.8 dB for CuCoF1-rGO-TPU, CuCoF2-rGO-TPU, and CuF3-rGO-TPU nanocomposites, respectively, at a thickness of 1 mm. The highly efficient EMI shielding performance was attributed to the good impedance matching, conductive, dielectric, and magnetic loss. The demonstrated nanocomposites are promising candidates for a lightweight, flexible, and highly efficient EMI shielding material

Mechanical, thermal, electrical characteristics and emi absorption shielding effectiveness of rubber composites based on ferrite and carbon fillers

In this work, rubber composites were fabricated by incorporation of manganese-zinc ferrite alone and in combination with carbon-based fillers into acrylonitrile-butadiene rubber. Electromagnetic parameters and electromagnetic interference (EMI) absorption shielding effectiveness of composite materials were examined in the frequency range 1 MHz–3 GHz. The influence of ferrite and fillers combination on thermal characteristics and mechanical properties of composites was investigated as well. The results revealed that ferrite imparts absorption shielding efficiency to the composites in tested frequency range. The absorption shielding effectiveness and absorption maxima of ferrite filled composites shifted to lower frequencies with increasing content of magnetic filler. The combination of carbon black and ferrite also resulted in the fabrication of efficient EMI shields. However, the EMI absorption shielding effectiveness was lower, which can be ascribed to higher electrical conductivity and higher permittivity of those materials. The highest conductivity and permittivity of composites filled with combination of carbon nanotubes and ferrite was responsible for the lowest absorption shielding effectiveness within the examined frequency range. The results also demonstrated that combination of ferrite with carbon-based fillers resulted in the enhancement of thermal conductivity and improvement of mechanical properties. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.Slovak Research and Development AgencySlovak Research and Development Agency [APVV-16-0136, APVV-19-0091]Agentúra na Podporu Výskumu a Vývoja, APVV: APVV-16-0136, APVV-19-009

Size dependent heating efficiency of iron oxide single domain nanoparticles

The iron oxide nanoparticles have been synthesized by coprecipitation and solvothermal reduction methods. The particles obtained differ in size, the mean size of particles coprecipitated is of 13 nm and the particles, prepared by solvothermal reduction method have a size of 20 nm. Both kinds of nanoparticles demonstrate narrow particles sizes distribution. The particles which are prepared by coprecipitation method have narrow particles sizes distribution with mean size diameter of 13 nm and the particles, prepared by solvothermal reduction method have a size of 20 nm. The X-ray diffraction data analysis revealed that highly crystalline and single-phase magnetite nanoparticles are formed by solvothermal reduction technique, whereas coprecipitation leads to the formation of multi-phase composition of a magnetite (72%) and maghemite (28%). According to the size of nanoparticles obtained, they are in superparamagnetic state for iron oxides. The saturation magnetization of solvothermal prepared particles is higher than those for coprecipitated due to their higher crystallinity and phase purity. Nevertheless, the glycerol dispersion of particles coprecipitated shows higher SLP values than the dispersion of the particles, synthesized by solvothermal reduction method. The heating efficiency of nanoparticles based dispersions is explained by the particles size effect and properties of carrier medium. © 2015 The Authors

Lightweight, flexible and high-performance nanocomposites based on reduced graphene oxide and spinel ferrite (ZnFe2O4 / CoFe2O4) nanoparticles in thermoplastic polyurethane matrix for electromagnetic interference shielding applications

Lightweight and flexible material with enhanced electromagnetic interference shielding effectiveness is highly in demand in the electronics and communication industry. Herein, we synthesized CoFe2O4 and ZnFe2O4 nanoparticles using the sonochemical method, and further, these nanoparticles were embedded inside thermoplastic polyurethane (TPU) along with reduced graphene oxide (rGO) by a melt-mixing approach using a microcompounder. CoFe2O4 or ZnFe2O4 nanocomposites in the TPU matrix with rGO showed outstanding electromagnetic shielding performance having a constant thickness of 0.80 mm, only. The maximum total shielding effectiveness (SET) was 48.3 dB for ZnFe2O4 nanocomposite and 50.76 dB for CoFe2O4 nanocomposite. These results indicate that the developed nanocomposite can be potentially utilized for electromagnetic shielding applications. © 2021 NANOCON Conference Proceedings - International Conference on Nanomaterials. All rights reserved.Grantová Agentura České Republiky, GA ČR; Univerzita Tomáše Bati ve Zlíně; Leibniz-Institut für Polymerforschung Dresden, IP

Preparation and properties of novel binary and ternary highly amorphous poly(vinyl alcohol)-based composites with hybrid nanofillers

Smart protective coatings and devices are currently of great interest. In particular, they can absorb or reflect harmful waves of electromagnetic interference (EMI). In this work, novel binary and ternary composites with highly amorphous poly(vinyl alcohol) (HAVOH) as a matrix and single-walled carbon nanotubes (SWCNTs) and MXenes as nanofillers were prepared. HAVOH is a recently patented kind of poly(vinyl alcohol) (PVOH) that was modified with diol monomers. MXenes are a new type of inorganic two-dimensional (2D) nanoparticle consisting of carbides, nitrides and carbonitrides. Three series of composites, HAVOH/SWCNTs, HAVOH/MXenes and HAVOH/SWCNTs/MXenes, were prepared using the solvent casting method. Samples were tested with various methods to study their structure, electrical properties, thermal behavior and EMI-shielding properties. HAVOH/3.0 wt.% SWCNTs/3.0 wt.% MXene specimens revealed a shielding effectiveness of 55 dB, which is 122 times better than that of the neat matrix. These results are promising for the fabrication of films with protective effects against EMI.Drexel University; Horizon 2020 Framework Programme, H2020; H2020 Marie Skłodowska-Curie Actions, MSCA, (777810, APVV 19–0465, VEGA 02/0006/22); European Cooperation in Science and Technology, COST, (CA19118)Authors greatly appreciate Prof. Yury Gogotsi and Dr. Christopher Shuck (Drexel University, USA) for providing the MXene paste