Shadab Dabagh

Synthesis, characterization and in vitro evaluation of exquisite targeting SPIONs-PEG-HER in HER2+ human breast cancer cells.

A stable, biocompatible and exquisite SPIONs-PEG-HER targeting complex was developed. Initially synthesized superparamagnetic iron oxide nanoparticles (SPIONs) were silanized using 3-aminopropyltrimethoxysilane (APS) as the coupling agent in order to allow the covalent bonding of polyethylene glycol (PEG) to the SPIONs to improve the biocompatibility of the SPIONs. SPIONs-PEG were then conjugated with herceptin (HER) to permit the SPIONs-PEG-HER to target the specific receptors expressed over the surface of the HER2+ metastatic breast cancer cells. Each preparation step was physico-chemically analyzed and characterized by a number of analytical methods including AAS, FTIR spectroscopy, XRD, FESEM, TEM, DLS and VSM. The biocompatibility of SPIONs-PEG-HER was evaluated in vitro on HSF-1184 (human skin fibroblast cells), SK-BR-3 (human breast cancer cells, HER+), MDA-MB-231 (human breast cancer cells, HER-) and MDA-MB-468 (human breast cancer cells, HER-) cell lines by performing MTT and trypan blue assays. The hemolysis analysis results of the SPIONs-PEG-HER and SPIONs-PEG did not indicate any sign of lysis while in contact with erythrocytes. Additionally, there were no morphological changes seen in RBCs after incubation with SPIONs-PEG-HER and SPIONs-PEG under a light microscope. The qualitative and quantitative in vitro targeting studies confirmed the high level of SPION-PEG-HER binding to SK-BR-3 (HER2+ metastatic breast cancer cells). Thus, the results reflected that the SPIONs-PEG-HER can be chosen as a favorable biomaterial for biomedical applications, chiefly magnetic hyperthermia, in the future.

Cu2+ and Al3+ co-substituted cobalt ferrite: structural analysis, morphology and magnetic properties

Cu–Al substituted Co ferrite nanopowders, Co1−xCuxFe2−xAl xO4 (0.0 ≤ x ≤ 0.8) were synthesized by the co-precipitation method. The effect of Cu–Al substitution on the structural and magnetic properties have been investigated. X-ray diffraction (XRD) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FESEM) and vibrating sample magnetometer (VSM) are used for studying the effect of variation in the Cu–Al substitution and its impact on particle size, magnetic properties such as Ms and Hc. Cu–Al substitution occurs and produce a secondary phase, α-Fe 2O3. The crystallite size of the powder calcined at 800 ∘C was in the range of 19–26 nm. The lattice parameter decreases with increasing Cu–Al content. The nanostructural features were examined by FESEM images. Infrared absorption (IR) spectra shows two vibrational bands; at around 600 (v1) and 400 cm −1 (v2). They are attributed to the tetrahedral and octahedral group complexes of the spinel lattice, respectively. It was found that the physical and magnetic properties have changed with Cu–Al contents. The saturation magnetization decreases with the increase in Cu–Al substitution. The reduction of coercive force, saturation magnetization and magnetic moments are may be due to dilution of the magnetic interaction.

Synthesis, functionalization, characterization, and in vitro evaluation of robust pH-sensitive CFNs–PA–CaCO3

The preparation, characterization, and application of Papain (PA) conjugated CaCO3-coated cobalt ferrite nanoparticles (CFNs–PA–CaCO3) is reported. Papain was covalently attached onto silanized cobalt ferrite nanoparticles (CFNs–APS) and then coated with robust pH sensitive CaCO3. It was characterized by FTIR, XRD, TEM, FESEM, and TGA. The release behaviour of PA from functionalized nanoparticles in acidic and physiological pH was investigated. However, the rate of PA release was slow and enhanced with time at physiological pH; the results illustrate that acidic conditions disassembles the coating, which caused a rapid release of PA. The biocompatibility evaluation of CFNs/CFNs–CaCO3 and the cytotoxicity of free PA/CFNs–PA was carried out in vitro on human breast cancer cells (MDA-MB-231) and human skin fibroblast cells (HSF 1184) by performing an MTT assay. An improved cytotoxic effect was obtained for PA conjugated cobalt ferrites in comparison with free PA. The synthesized delivery system was perfectly tolerable to the blood and cells in concentrations below 200 μg mL−1. Investigations were followed out to measure the time and dose dependent cellular uptake of functionalized nanoparticles via the Prussian blue staining method under an inverted microscope, which indicated that functionalized nanoparticles showed internalization properties. The results conveyed that the synthesized system is a promising biomaterial for future biomedical applications, mainly cancer therapy. The present in vitro findings require comparison with those of in vivo studies.

Effects of Mg substitution on the structural and magnetic properties of Co0.5Ni0.5-xMgxFe2O4 nanoparticle ferrites

In this study, nanocrystalline Co-Ni-Mg ferrite powders with composition Co0.5Ni0.5-xMgxFe2O4 are successfully synthesized by the co-precipitation method. A systematic investigation on the structural, morphological and magnetic properties of un-doped and Mg-doped Co-Ni ferrite nanoparticles is carried out. The prepared samples are characterized using x-ray diffraction (XRD) analysis, Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), and vibrating sample magnetometry (VSM). The XRD analyses of the synthesized samples confirm the formation of single-phase cubic spinel structures with crystallite sizes in a range of similar to 32 nm to similar to 36 nm. The lattice constant increases with increasing Mg content. FESEM images show that the synthesized samples are homogeneous with a uniformly distributed grain. The results of IR spectroscopy analysis indicate the formation of functional groups of spinel ferrite in the co-precipitation process. By increasing Mg2+ substitution, room temperature magnetic measurement shows that maximum magnetization and coercivity increase from similar to 57.35 emu/g to similar to 61.49 emu/g and similar to 603.26 Oe to similar to 684.11 Oe (1 Oe = 79.5775 A.m(-1)), respectively. The higher values of magnetization M-s and M-r suggest that the optimum composition is Co0.5Ni0.4Mg0.1Fe2O4 that can be applied to high-density recording media and microwave devices.

Fast Faraday cup for fast ion beam TOF measurements in deuterium filled plasma focus device and correlation with Lee model

In this work, the design and construction of a 50 Ω fast Faraday cup and its results in correlation with the Lee Model Code for fast ion beam and ion time of flight measurements for a Deuterium filled plasma focus device are presented. Fast ion beam properties such as ion flux, fluence, speed, and energy at 2–8 Torr Deuterium are studied. The minimum 34 ns full width at half maximum ion signal at 12 kV, 3 Torr Deuterium in INTI PF was captured by a Faraday cup. The maximum ion energy of 67 ± 5 keV at 4 Torr Deuterium was detected by the Faraday cup. Ion time of flight measurements by the Faraday cup show consistent correlation with Lee Code results for Deuterium especially at near to optimum pressures.

The Effect of Sintering Temperature on the Structural and Magnetic Properties of Ni-Mg Substituted CoFe2O4 Nanoparticles

This study evaluates the structural and magnetic properties of Ni-Mg substituted Cobalt ferrite samples prepared through the co-precipitation method. The nominal compositions Co0.5Ni0.5−xMgx Fe2O4 in the range x = 0.1 have been synthesized and then was sintered at temperature at 700 and 1000°C in the furnace for 10 hour with a heating rate of 5°C/min. The prepared nanoferrites were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and vibration sample magnetometer (VSM). XRD confirmed formation of single phase spinel ferrite with average crystalline size in the range of 27–33 nm. The lattice constant (a), cell volume (V) and X-ray density (ρx) are also calculated from XRD data. Lattice constant (a) decreases with an increase of sintering temperature. Further information about the structure and morphology of the nanoferrites was obtained from FESEM and results are in good agreement with XRD. Saturation magnetization showed increasing trend with sintering temperature from 700 to 1000°C.