Submicron Structure in Biocompatible Ferrofluids

Abstract

This paper presents a comparative study between the microstructural features of two water-ferrofluids intended for biological applications. In both cases the ferrophase was prepared by auto-catalytic reaction between ferrous and ferric salts and resulted in magnetite and some maghemite precipitates. The difference is given by the stabilizer molecule: tetramethylammonium hydroxide and, respectively, citric acid. Transmission electron microscopy and atomic force microscopy were utilized for ferrophase size investigation. The evidence of short chains and large aggregates was obtained mainly by atomic force microscopy analysis (the tip diameter being equal to 5 nm). Their role in the ferrofluid rheological properties was studied by carrying out comparative measurements of viscosity and surface tension. Complementary investigation of the ferrofluid composition was done by means of IR absorption spectra. The suitability of the prepared ferrofluids for biological goals was proved by their convenient ferrophase diameter as well as by their stability in time.

Environment-Friendly Magnetic Fluids for Wastewater Remediation - Synthesis and Characterization

“…The choice of organic agents for magnetic core capping is crucial for both the long term stability of the NPs in the ferrouid and their eciency and non-toxicity in the application they were designed for. Citric acid is a well-known stabilizing agent [6], while antioxidant compounds such as tannic acid or high content polyphenols mixture from green tea extract were only more recently taken into consideration as good stabilizing/capping compounds for various types of NPs [3].…”

Atomic force microscopy in the study of ferrofluids

“…More, this way the ferrofluid is assured also against the gravitational and magnetic field sedimentation. The physical characterization of the ferrofluid discussed inhere was presented in [12] where the formation of iron citrate at the ferrophase particles was demonstrated by infrared spectroscopy. The 3-D image provided by AFM technique allows visualising and measuring the aggregate height so one can say that solid particles rather form packages having the same height as the individual components than overlapped clusters.…”

Synthesis protocol influence on aqueous magnetic fluid properties

“…The properties of magnetic fluids have been intensively studied due to their multiple applications [5,6], in both technical and life sciences. Magnetite nanoparticles with superparamagnetic properties have great potential to achieve convenient properties for biomedical applications due to their biocompatibility, it is known that the human body contains around 3 g Fe within the proteins like ferritin, hemosiderin, transferritin and hemoglobin and, also that the iron oxides are gradually recycled naturally.…”