Preparation of superparamagnetic iron oxide nanoparticles and investigation of their interaction with cells

Abstract

Superparamagnetic iron oxide nanoparticles (SPIONs) have been widely studied in biomedical applications such as bioimaging through magnetic resonance imaging and drug delivery. The successful uses of SPIONs depend on nanoparticles stability in biological environment and their interactions with cells. Hence these two factors are crucial for improvement of nanoparticle design in these applications. In this work, SPIONs were synthesized with silica (S-SPIONs) and amine (A-SPIONs) surface modifications providing hydroxyl and amine functionalities, respectively. The colloidal stabilities of SPIONs were evaluated as hydrodynamic size in different biological relevance media. The results showed that bare SPIONs were unstable and highly aggregated when exposed to cell culture media. Coating with silica and amine could effectively stabilized the nanoparticles as evidenced by reduction of hydrodynamic diameters. In addition to surface modification, supplementation of serum proteins to cell culture media also reduced the aggregations. Furthermore, both S-SPIONs and A-SPIONs showed no cytotoxicity effect on human breast cancer cells (MCF-7) with cell viability remained over 80%. Hence this study showed the role of surface modification of bare SPIONs with silica and amine functionalization and serum supplement to stabilize nanoparticle stability in biological environment. These two surface coating SPIONs were not only non-toxic to the cells, but also have surface functionalities that could be further conjugated with desired biomolecules for more specific targeting especially in cancer targeting for diagnosis or therapeutic applications.

External Field‐Driven Untethered Microrobots for Targeted Cargo Delivery

“…SPIONs can be magnetized by external magnetic sources while having zero magnetization in the absence of an external magnetic field, which provides additional biological stability. [ 21 ] They are usually embedded inside [ 22 ] or absorbed onto the surface [ 19b ] of UMRs during the fabrication process. However, SPIONs tend to accumulate together and have a low dispersibility in water due to their hydrophobicity.…”

Characteristics of a small colony variant of Pseudomonas putida F1 emerged from repetitive exposure to nanoscale zerovalent iron

“…The presence of NZVI or Fe(II) significantly promoted the Fenton-mediated oxidative damage, thus increasing chance of phenotypic variation or stress-response induced tolerance against gentamicin. Unlike the reactive iron nanoparticles, the iron oxide nanoparticle can interact with the biomolecules, yet, non-toxic to cells [18]. Even though Fe(III) and O-NZVI (which mainly consists of Fe(III)) can also interact with O -2 • or H 2 O 2 resulting in Fe(II) and oxygen, the lower impact of Fe(III) on bacterial cells is likely due to their low solubility, thus reducing their bioavailability [19].…”

Study of the surface structure of Fe quantum wire prepared by electrochemical method in solution

“…When the size of the materials and device is reduced to nanometer scale, many novel quantum phenomena will appear, which will bring many new and important applications [1][2][3]. A typical case is the quantum conductance behavior of the atomically thin metal junction, which has been verified with a large number of theoretical and experimental studies in the past decades [4][5][6].…”