SYNTHESIS OF PEG-ENCAPSULATED SUPERPARAMAGNETIC COLLOIDAL NANOCRYSTALS CLUSTERS

NANO ◽  
2010 ◽  
Vol 05 (06) ◽  
pp. 333-339 ◽  
Author(s):  
HUI WANG ◽  
YIMING LI ◽  
ZHAOFENG LUO ◽  
SHUAI ZHOU ◽  
JIN SHENG ◽  
...  

PEG-encapsulated colloidal nanocrystal clusters (CNCs) have been synthesized via a one-step solvothermal process at a temperature of 230°C. The composition, phase, and morphology of these CNCs have been characterized by X-ray diffraction and transmission electron microscopy. Studies show that each particle is a cluster structure consisting of small primary iron oxide nanocrystals. Magnetic measurements reveal the superparamagnetic nature of these CNCs at room temperature. The CNCs with different sizes (80 nm or 95 nm) can be obtained by changing the time of reaction. The dispersibility and colloidal stability of these CNCs with PEG as the major surface group have also been discussed. In vitro cytotoxicity of these CNCs with different thickness PEG layer on HeLa cell has also been assayed. Cytotoxicity results reveal that the CNCs concentration and the incubation time can influence the cell viability, and the size of CNCs almost does not affect the cell viability.

2019 ◽  
Vol 13 (2) ◽  
pp. 114-128 ◽  
Author(s):  
Gayatri Patel ◽  
Bindu K.N. Yadav

Background: The purpose of this study was to formulate, characterize and conduct in vitro cytotoxicity of 5-fluorouracil loaded polymeric electrospun nanofibers for the treatment of skin cancer. The patents on electrospun nanofibers (US9393216B2), (US14146252), (WO2015003155A1) etc. helped in the selection of polymers and method for the preparation of nanofibers. Methods: In the present study, the fabrication of nanofibers was done using a blend of chitosan with polyvinyl alcohol and processed using the electrospinning technique. 5-fluorouracil with known chemotherapeutic potential in the treatment of skin cancer was used as a drug carrier. 24-1 fractional factorial screening design was employed to study the effect of independent variables like the concentration of the polymeric solution, applied voltage (kV), distance (cm), flow rate (ml / hr) on dependent variables like % entrapment efficiency and fiber diameter. Results: Scanning electron microscopy was used to characterize fiber diameter and morphology. Results showed that the fiber diameter of all batches was found in the range of 100-200 nm. The optimized batch results showed the fiber diameter of 162.7 nm with uniform fibers. The tensile strength obtained was 190±37 Mpa. Further in vitro and ex vivo drug release profile suggested a controlled release mechanism for an extended period of 24 hr. The 5-fluorouracil loaded electrospun nanofibers were found to decrease cell viability up to ≥50% over 24 hr, with the number of cells dropping by ~ 10% over 48 hr. As the cell viability was affected by the release of 5-fluorouracil, we believe that electrospun nanofibers are a promising drug delivery system for the treatment of Basal Cell Carcinoma (BCC) skin cancer. Conclusion: These results demonstrate the possibility of delivering 5-Fluorouracil loaded electrospun nanofiber to skin with enhanced encapsulation efficiency indicating the effectiveness of the formulation for the treatment of basal cell carcinoma type of skin cancer.


2021 ◽  
Vol 3 (7) ◽  
Author(s):  
Alexandre Pancotti ◽  
Dener Pereira Santos ◽  
Dielly Oliveira Morais ◽  
Mauro Vinícius de Barros Souza ◽  
Débora R. Lima ◽  
...  

AbstractIn this study, we report the synthesis and characterization of NiFe2O4 and CoFe2O4 nanoparticles (NPs) which are widely used in the biomedical area. There is still limited knowledge how the properties of these materials are influenced by different chemical routes. In this work, we investigated the effect of heat treatment over cytotoxicity of cobalt and niquel ferrites NPs synthesized by sol-gel method. Then the samples were studied using transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), vibrating sample magnetometer (VSM), Fourier Transform Infrared Spectroscopy Analysis (FTIR), and X-ray fluorescence (XRF). The average crystallite sizes of the particles were found to be in the range of 20–35 nm. The hemocompatibility (erythrocytes and leukocytes) was checked. Cytotoxicity results were similar to those of the control test sample, therefore suggesting hemocompatibility of the tested materials.


2020 ◽  
Vol 10 (12) ◽  
pp. 4324 ◽  
Author(s):  
Sergei S. Vlasov ◽  
Pavel S. Postnikov ◽  
Mikhail V. Belousov ◽  
Sergei V. Krivoshchekov ◽  
Mekhman S. Yusubov ◽  
...  

Hybrid microparticles based on an iron core and an amphiphilic polymeric shell have been prepared to respond simultaneously to magnetic and ultrasonic fields and variation in the surrounding pH to trigger and modulate the delivery of doxorubicin. The microparticles have been developed in four steps: (i) synthesis of the iron core; (ii) surface modification of the core; (iii) conjugation with the amphiphilic poly(lactic acid)-grafted chitosan; and (iv) doxorubicin loading. The particles demonstrate spherical shape, a size in the range of 1–3 µm and surface charge that is tuneable by changing the pH of the environment. The microparticles demonstrate good stability in simulated physiological solutions and are able to hold up to 400 µg of doxorubicin per mg of dried particles. The response to ultrasound and the changes in the shell structure during exposure to different pH levels allows the control of the burst intensity and release rate of the payload. Additionally, the magnetic response of the iron core is preserved despite the polymer coat. In vitro cytotoxicity tests performed on fibroblast NIH/3T3 demonstrate a reduction in the cell viability after administration of doxorubicin-loaded microparticles compared to the administration of free doxorubicin. The application of ultrasound causes a burst in the release of the doxorubicin from the carrier, causing a decrease in cell viability. The microparticles demonstrate in vitro cytocompatibility and hemocompatibility at concentrations of up to 50 and 60 µg/mL, respectively.


Toxins ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 14 ◽  
Author(s):  
Danielle Henn ◽  
Annette Venter ◽  
Christo Botha

Consumption of bufadienolide-containing plants are responsible for many livestock mortalities annually. Bufadienolides are divided into two groups; non-cumulative bufadienolides and cumulative bufadienolides. Cumulative bufadienolides are referred to as neurotoxic, as the chronic intoxication with this type of bufadienolide results in a paretic/paralytic syndrome known as ‘krimpsiekte’. The in vitro cytotoxicity of a non-cumulative bufadienolide, 1α,2α-epoxyscillirosidine, and a cumulative bufadienolide, lanceotoxin B, were compared using the MTT ((3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide reduction) assay after exposing rat myocardial (H9c2) and mouse neuroblastoma (Neuro-2a) cell lines. The effect of these two bufadienolides on cell ultrastructure was also investigated using transmission electron microscopy (TEM). H9c2 cells exhibited greater cytotoxicity when exposed to 1α,2α-epoxyscillirosidine, compared to lanceotoxin B. In contrast, Neuro-2a cells were more susceptible to lanceotoxin B. The EC50 (half maximal effective concentration) of lanceotoxin B exposure of Neuro-2a cells for 24–72 h ranged from 4.4–5.5 µM compared to EC50s of 35.7–37.6 µM for 1α,2α-epoxyscillirosidine exposure of Neuro-2a cells over the same period. 1α,2α-Epoxyscillirosidine induced extensive vacuolization in both cell types, with swollen RER (rough endoplasmic reticulum) and perinuclear spaces. Lanceotoxin B caused swelling of the mitochondria and sequestration of cytoplasmic material within autophagic vesicles. These results corroborate the notion that cumulative bufadienolides are neurotoxic.


Nanomedicine ◽  
2020 ◽  
Vol 15 (25) ◽  
pp. 2433-2445
Author(s):  
Joel Kuhn ◽  
Giorgos Papanastasiou ◽  
Cheuk-Wai Tai ◽  
Carmel M Moran ◽  
Maurits A Jansen ◽  
...  

Aim: To examine the multimodal contrasting ability of gold-dotted magnetic nanoparticles (Au*MNPs) for magnetic resonance (MR), computed tomography (CT) and intravascular ultrasound (IVUS) imaging. Materials & methods: Au*MNPs were prepared by adapting an impregnation method, without using surface capping reagents and characterized (transmission electron microscopy, x-ray diffraction and Fourier-transform infrared spectroscopy) with their in vitro cytotoxicity assessed, followed by imaging assessments. Results: The contrast-enhancing ability of Au*MNPs was shown to be concentration-dependent across MR, CT and IVUS imaging. The Au content of the Au*MNP led to evident increases of the IVUS signal. Conclusion: We demonstrated that Au*MNPs showed concentration-dependent contrast-enhancing ability in MRI and CT imaging, and for the first-time in IVUS imaging due to the Au content. These Au*MNPs are promising toward solidifying tri-modal imaging-based theragnostics.


Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1552
Author(s):  
Asmaa M. Abd El-Aziz ◽  
Azza El-Maghraby ◽  
Andrea Ewald ◽  
Sherif H. Kandil

Electrospun carbon nanofibers (CNFs), which were modified with hydroxyapatite, were fabricated to be used as a substrate for bone cell proliferation. The CNFs were derived from electrospun polyacrylonitrile (PAN) nanofibers after two steps of heat treatment: stabilization and carbonization. Carbon nanofibrous (CNF)/hydroxyapatite (HA) nanocomposites were prepared by two different methods; one of them being modification during electrospinning (CNF-8HA) and the second method being hydrothermal modification after carbonization (CNF-8HA; hydrothermally) to be used as a platform for bone tissue engineering. The biological investigations were performed using in-vitro cell counting, WST cell viability and cell morphology after three and seven days. L929 mouse fibroblasts were found to be more viable on the hydrothermally-modified CNF scaffolds than on the unmodified CNF scaffolds. The biological characterizations of the synthesized CNF/HA nanofibrous composites indicated higher capability of bone regeneration.


Author(s):  
BHABANI SANKAR SATAPATHY ◽  
JNANRANJAN PANDA

Objective: Successful treatment of glioma still remains a tough challenge. The present study aims at the development and evaluation of carmustine loaded nanosize phospholipid vesicles (CNLVs) for the treatment of glioma. Methods: The experimental NLVs were developed by conventional lipid layer hydration technique and were characterized by different in vitro tools such as diffraction light scattering (DLS), zeta potential, field emission scanning electron microscopy (FESEM), cryo-transmission electron microscopy (cryo-TEM), in vitro drug loading capacity, drug release study etc. In vitro cytotoxicity and cellular uptake of the optimized drug-loaded NLVs were carried out in U87MG human glioblastoma cell line. In vivo pharmacokinetic study was conducted in Swiss albino mice. Results: DLS data showed an average vesicle diameter of 92 nm with narrow size distribution. Optimized CNLVs were spherical in shape with a smooth surface as depicted from FESEM data. Cryo-TEM study confirmed formation of unilamellar vesicles with intact outer bilayer. A reasonable drug loading of 7.8 % was reported for the optimized CNLVs along with a sustained release of CS over a 48 h study period. In vitro cytotoxicity assay revealed a considerable higher toxicity of CNLVs than free drugs in the U87MG cells. Confocal microscopy showed a satisfactory internalization of the optimized drug-loaded NLVs in the tested cell line. Pharmacokinetic data demonstrated an enhanced mean residence time of optimized CNLVs in blood than free drug. Conclusion: Results depicted the potential of experimental CNLVs for the treatment of glioma after further in vivo tests.


Author(s):  
Sherifat Banke Idris ◽  
Abdul Kadir Arifah ◽  
Faez Firdaus Abdullah Jesse ◽  
Siti Zubaidah Ramanoon ◽  
Muhammad Abdul Basit ◽  
...  

Background: Evaluation of the toxic effects of nanoparticle-drug in vitro is an important step in the design of new pharmaceutical formulations. Rapid results, reduced cost and easy handling makes cell culture models first line in initial toxicological assessment of nanodrug preparations. Objective: To evaluate the in vitro cytotoxicity of oxytetracycline loaded calcium carbonate aragonite nanoparticle in normal mouse fibroblast (NIH3T3) cell line. Method: NIH3T3 cells were exposed to varying concentrations (6.25 - 100µg/mL) of calcium carbonate aragonite nanoparticle (CS-CaCO3NP), oxytetracycline loaded calcium carbonate aragonite nanoparticle (OTC-CS-CaCO3NP) and oxytetracycline (OTC) in 96 well plates for 24, 48 and 72 hours. Cell viability was determined by MTT and trypan blue assays. Result: Both assays show that CS-CaCO3NP and OTC-CS-CaCO3NP had higher cell viability values compared to OTC. Conclusion: Encapsulating OTC into CS-CaCO3NP reduced its cytotoxicity to NIH3T3 cells using both MTT and trypan blue assay.


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