Cobalt nanoparticles for biomedical applications: Facile synthesis, physiochemical characterization, cytotoxicity behavior and biocompatibility

Abstract

Cobalt (Co) nanoparticles (NPs) were produced by a simple, one step hydrothermal method with the capping of oleic acid. Intrinsic structural, physiochemical and magnetic properties of Co NPs were investigated and demonstrated their applicability in biomedicine. X-ray diffraction, Raman spectroscopy and infrared (IR) spectroscopic studies confirm the single phase Co NPs with a high structural quality. The IR data revealed the capping of oleic acid via monodentate interaction. Small angle scattering studies suggest the existence of sticky hard sphere type of interaction among the Co NPs because of magnetic interaction which is further evidenced by electron microscopy imaging analyses. The Co NPs exhibit a ferromagnetic character over a wide range of temperature (20-300 K). The temperature dependence of magnetic parameters namely, saturation magnetization, remanent magnetization, coercivity and reduced remanent magnetization were determined and correlated with structure of Co NPs. The Cytotoxicity studies demonstrate that these Co NPs exhibit the mild anti-proliferative character against the cancer cells (cisplatin resistant ovarian cancer (A2780/CP70)) and safe nature towards the normal cells. Haemolytic behaviour of human red blood cells (RBC) revealed (<5%) haemolysis signifying the compatibility of Co NPs with human RBC which is an essential feature in vivo biomedical applications without creating any harmful effects in the human blood stream.

Binding modes of carboxylic acids on cobalt nanoparticles

“…They interpreted the shift of the carbonyl's IR band to be due to a bridging bidentate adsorption. Similarly, Ansari et al 35 presented an IR spectrum that demonstrated the chemisorption of the acid as a carboxylate onto the nanoparticles. However, they attributed the shift of the carbonyl band to a monodentate interaction.…”

“…46 The whole system was placed in a cubic box of 25 Å a side and equilibrated in the NVT ensemble during 3 ps of Born-Oppenheimer molecular dynamics. A Nosé-Hoover thermostat 47 was set to 500 K, in accordance with the temperature of experiments (160-250 1C), 27,34,35 and a time step of 1 fs was used for the integration of the equations of motion. Fluctuations in temperature, potential energy, and Co-O bonds during the equilibration are shown in Fig.…”

“…1. The most recent experimental study conducted on the OA-cobalt nanoparticle system by Ansari et al 35 suggested a monodentate-type interaction, which was hence taken as the starting structure. During the equilibration, we observed that the oxygen atom which was not bound to the nanoparticle surface attached to a neighbouring cobalt atom within less than 0.25 ps (Fig.…”

Cobalt nanoparticles mechanically deposited on α‐Al2O3: a competitive catalyst for the production of hydrogen through ethanol steam reforming

“…5,6 Most of this work has been devoted to precious metal nanoparticles such as gold, 7 palladium 8 and platinum, 9 which display very high activity. Although unsupported cobalt (Co) nanoparticles (CoNPs) are of interest in several fields, 10,11 few studies have been reported concerning the potential application of CoNPs in catalysis, mostly applied in low-temperature liquid-phase reactions. [12][13][14] In fact, the thermal stability of unsupported metal nanoparticles is generally poor, their applicability being usually limited to liquid-phase reactions performed at low temperature; alternatively, they may be essentially regarded as model catalysts, whose activity is limited to short time-on-stream experiments.…”

Influence of the cobalt nitrate:ethylene glycol molar ratio on the formation of carboxylate precursors and cobalt oxides

“…Due to their exceptional attributes and reduced dimensions, they can be exploited in a large range of fields [1]. Cobalt oxides are important materials with a wide array of applications, such as, catalysts [2,3,4,5,6], different kind of sensors [7,2,4,5], lithium ion batteries [8,7,5], optoelectronic devices [9,10], combustion of hydrocarbons at gas purification [11], supercapacitors [12,13], Fisher-Tropsh syntheses [14] and biomedical sciences [1,7,12].…”