Colloidal Stability and Magnetophoresis of Gold-Coated Iron Oxide Nanorods in Biological Media

2012 ◽  
Vol 116 (42) ◽  
pp. 22561-22569 ◽  
Author(s):  
Swee Pin Yeap ◽  
Pey Yi Toh ◽  
Abdul Latif Ahmad ◽  
Siew Chun Low ◽  
Sara A. Majetich ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Colloidal Stability ◽  
Biological Media ◽  
Oxide Nanorods

scholarly journals Colloidal Stability of Aqueous Suspensions of Polymer-Coated Iron Oxide Nanorods: Implications for Biomedical Applications

2018 ◽  
Vol 1 (12) ◽  
pp. 6760-6772 ◽  
Author(s):  
J. A. Marins ◽  
T. Montagnon ◽  
H. Ezzaier ◽  
Ch. Hurel ◽  
O. Sandre ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Biomedical Applications ◽  
Colloidal Stability ◽  
Aqueous Suspensions ◽  
Oxide Nanorods

scholarly journals Macrophage-Laden Gold Nanoflowers Embedded with Ultrasmall Iron Oxide Nanoparticles for Enhanced Dual-Mode CT/MR Imaging of Tumors

Pharmaceutics ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 995
Author(s):  
Yucheng Peng ◽  
Xiaomeng Wang ◽  
Yue Wang ◽  
Yue Gao ◽  
Rui Guo ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Mr Imaging ◽  
Iron Oxide Nanoparticles ◽  
Colloidal Stability ◽  
Pamam Dendrimer ◽  
Great Promise ◽  
Oxide Nanoparticles ◽  
Dual Mode ◽  
Gold Nanoflowers ◽  
Average Size

The design of multimodal imaging nanoplatforms with improved tumor accumulation represents a major trend in the current development of precision nanomedicine. To this end, we report herein the preparation of macrophage (MA)-laden gold nanoflowers (NFs) embedded with ultrasmall iron oxide nanoparticles (USIO NPs) for enhanced dual-mode computed tomography (CT) and magnetic resonance (MR) imaging of tumors. In this work, generation 5 poly(amidoamine) (G5 PAMAM) dendrimer-stabilized gold (Au) NPs were conjugated with sodium citrate-stabilized USIO NPs to form hybrid seed particles for the subsequent growth of Au nanoflowers (NFs). Afterwards, the remaining terminal amines of dendrimers were acetylated to form the dendrimer-stabilized Fe3O4/Au NFs (for short, Fe3O4/Au DSNFs). The acquired Fe3O4/Au DSNFs possess an average size around 90 nm, display a high r1 relaxivity (1.22 mM−1 s−1), and exhibit good colloidal stability and cytocompatibility. The created hybrid DSNFs can be loaded within MAs without producing any toxicity to the cells. Through the mediation of MAs with a tumor homing and immune evasion property, the Fe3O4/Au DSNFs can be delivered to tumors more efficiently than those without MAs after intravenous injection, thus significantly improving the MR/CT imaging performance of tumors. The developed MA-mediated delivery system may hold great promise for enhanced tumor delivery of other contrast agents or nanomedicines for precision cancer nanomedicine applications.

scholarly journals The Effect of pH and Viscosity on Magnetophoretic Separation of Iron Oxide Nanoparticles

2021 ◽  
Vol 7 (6) ◽  
pp. 80
Author(s):  
Leonie Wittmann ◽  
Chiara Turrina ◽  
Sebastian P. Schwaminger
Keyword(s):  
Iron Oxide ◽  
Iron Oxide Nanoparticles ◽  
Colloidal Stability ◽  
Downstream Processing ◽  
Physicochemical Characteristics ◽  
Particle Migration ◽  
Aggregation Behavior ◽  
Oxide Nanoparticles ◽  
Separation Processes ◽  
Effect Of Ph

Magnetic nanoparticles (MNPs) are used for magnetophoresis-based separation processes in various biomedical and engineering applications. Essential requirements are the colloidal stability of the MNPs and the ability to be separated even in low magnetic field gradients. Bare iron oxide nanoparticles (BIONs) with a diameter of 9.2 nm are synthesized via coprecipitation, exhibiting a high saturation magnetization of 70.84 Am2 kg−1 and no remanence. In our study, zeta potential, dynamic light scattering (DLS), and sedimentation analysis show that the aggregation behavior of BIONs is influenced by pH and viscosity. Small aggregate clusters are formed with either low or high pH values or increased viscosity. Regarding magnetophoresis-based separation, a higher viscosity leads to lower magnetophoretic velocities, similar to how small aggregates do. Additionally, cooperative magnetophoresis, the joint motion of strongly interacting particles, affects the separation of the BIONs, too. Our study emphasizes the effect of pH and viscosity on the physicochemical characteristics of MNPs, resulting in different aggregation behavior. Particularly, for high viscous working media in downstream processing and medicine, respectively, the viscosity should be taken into account, as it will affect particle migration.

LAPONITE®-stabilized iron oxide nanoparticles for in vivo MR imaging of tumors

2016 ◽  
Vol 4 (3) ◽  
pp. 474-482 ◽  
Author(s):  
Ling Ding ◽  
Yong Hu ◽  
Yu Luo ◽  
Jianzhi Zhu ◽  
Yilun Wu ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Mr Imaging ◽  
Iron Oxide Nanoparticles ◽  
Colloidal Stability ◽  
Coprecipitation Method ◽  
Oxide Nanoparticles

LAPONITE®-stabilized iron oxide nanoparticles with great colloidal stability and high T2 relaxivity are synthesized by a facile controlled coprecipitation method, and can significantly enhance the contrast of tumors in vivo, indicating their tremendous potential in MR imaging applications.

scholarly journals Influence of surface composition on the colloidal stability of ultra-small detonation nanodiamonds in biological media

2018 ◽  
Vol 83 ◽  
pp. 38-45 ◽  
Author(s):  
Carlo Bradac ◽  
Ishan Das Rastogi ◽  
Nicole M. Cordina ◽  
Alfonso Garcia-Bennett ◽  
Louise J. Brown
Keyword(s):  
Colloidal Stability ◽  
Surface Composition ◽  
Detonation Nanodiamonds ◽  
Biological Media

Size-Controllable Magnetic Iron Oxide Nanorods for Biomarker Targeting and Improving Microfluidic Mixing

2019 ◽  
Vol 2 (8) ◽  
pp. 3362-3371
Author(s):  
Yaolin Xu ◽  
Hui Wu ◽  
Qirong Xiong ◽  
Bing Ji ◽  
Hong Yi ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Microfluidic Mixing ◽  
Magnetic Iron Oxide ◽  
Oxide Nanorods

scholarly journals Cotransport of Cu with Graphene Oxide in Saturated Porous Media with Varying Degrees of Geochemical Heterogeneity

Water ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 444 ◽  
Author(s):  
Jianzhou He ◽  
Dengjun Wang ◽  
Tingting Fan ◽  
Dongmei Zhou
Keyword(s):  
Heavy Metals ◽  
Porous Media ◽  
Graphene Oxide ◽  
Iron Oxide ◽  
Colloidal Stability ◽  
Maximum Adsorption Capacity ◽  
Solution Ph ◽  
Physicochemical Conditions ◽  
Subsurface Environment ◽  
Geochemical Heterogeneity

Graphene oxide (GO) is likely to encounter heavy metals due to its widespread use and inevitable release into the subsurface environment, where the ubiquitous presence of iron oxides (e.g., hematite) would affect their interaction and transport. The present study aimed to investigate the cotransport of GO (20 mg L−1) and copper (0.05 mM CuCl2) in the presence of varying degrees of geochemical heterogeneity represented by iron oxide-coated sand fractions (ω = 0‒0.45) in water-saturated columns under environmentally relevant physicochemical conditions (1 mM KCl at pH 5.0‒9.0). The Langmuir-fitted maximum adsorption capacity of Cu2+ by GO reached 137.6 mg g−1, and the presence of 0.05 mM Cu2+ decreased the colloidal stability and subsequent transport of GO in porous media. The iron oxide coating was found to significantly inhibit the transport of GO and Cu-loaded GO in sand-packed columns, which can be explained by the favorable deposition of the negatively charged GO onto patches of the positively charged iron oxide coatings at pH 5.0. Increasing the solution pH from 5.0 to 9.0 promoted the mobility of GO, with the exception of pH 7.5, in which the lowest breakthrough of GO was observed. This is possibly due to the fact that the surface charge of iron oxide approaches zero at pH 7.5, suggesting that new “favorable” sites are available for GO retention. This study deciphered the complicated interactions among engineered nanomaterials, heavy metals, and geochemical heterogeneity under environmentally relevant physicochemical conditions. Our results highlight the significant role of geochemical heterogeneity, such as iron oxide patches, in determining the fate and transport of GO and GO-heavy metal association in the subsurface environment.

scholarly journals Coating Matters: Review on Colloidal Stability of Nanoparticles with Biocompatible Coatings in Biological Media, Living Cells and Organisms

2018 ◽  
Vol 25 (35) ◽  
pp. 4553-4586 ◽  
Author(s):  
Jonas Schubert ◽  
Munish Chanana
Keyword(s):  
Colloidal Stability ◽  
Biological Fluids ◽  
Chemical Properties ◽  
Coating Material ◽  
Living Systems ◽  
Biological Media ◽  
Coating Materials ◽  
Physico Chemical ◽  
Environment Temperature ◽  
To Come

Within the last two decades, the field of nanomedicine has not developed as successfully as has widely been hoped for. The main reason for this is the immense complexity of the biological systems, including the physico-chemical properties of the biological fluids as well as the biochemistry and the physiology of living systems. The nanoparticles’ physicochemical properties are also highly important. These differ profoundly from those of freshly synthesized particles when applied in biological/living systems as recent research in this field reveals. The physico-chemical properties of nanoparticles are predefined by their structural and functional design (core and coating material) and are highly affected by their interaction with the environment (temperature, pH, salt, proteins, cells). Since the coating material is the first part of the particle to come in contact with the environment, it does not only provide biocompatibility, but also defines the behavior (e.g. colloidal stability) and the fate (degradation, excretion, accumulation) of nanoparticles in the living systems. Hence, the coating matters, particularly for a nanoparticle system for biomedical applications, which has to fulfill its task in the complex environment of biological fluids, cells and organisms. In this review, we evaluate the performance of different coating materials for nanoparticles concerning their ability to provide colloidal stability in biological media and living systems.

Sign in / Sign up

Export Citation Format

Share Document