Iron oxide-based conjugates for cancer theragnostics

Abstract

In this paper we first summarize our recent research on fabrication and structure characterization of conjugates of Fe3O4 nanoparticles (MNPs) encapsulated by several organic materials such as oleic acid (OL), starch (ST), dextran (D), chitosan (CS), O-carboxymethyl chitosan (OCMCS) and the copolymer of poly(styrene-co-acrylic acid (St-co-AA)). The ferrofluids stability and toxicity were also considered. The magnetic inductive heating (MIH) curves were measured using a set up with an alternating (ac) magnetic field of strength of 40–100 Oe and frequency of 180–240 kHz. We then present new results dealing with attempting to apply the MNP/copolymer ferrofluid for treatment of Sarcoma 180 tumor. In vitro as well as ex vivo MIH experiments were carried out as preparation steps in order to estimate the proper conditions for the in vivo MIH experiment. As for the latter, we have successfully carried out the treatment of solid tumor of size around 6 × 6 mm inoculated on Swiss mice with use of a dose of 0.3–0.4 mg ml−1 ferrofluid injected subcutaneously into the tumor and field-irradiated for 30 min. Two groups of treated mice recovered in three weeks from MIH treatment three times during the first week. We finally show that curcumin loaded MNP-based conjugates showed themselves to be a potential agent for application as a bimodal contrast enhancer of magnetic resonance imaging (MRI) and fluorescence imaging. Additionally, in vitro and ex vivo studies by these two techniques evidenced that macrophage is capable of uptake and tends to carry the MNPs into a tumor.

On the reliable measurement of specific absorption rates and intrinsic loss parameters in magnetic hyperthermia materials

“…Experiments were performed in a custom-made setup that comprised a parafilm-covered plastic Eppendorf tube or glass vial containing the MNP sample, fibre-optic temperature measurement probes (Luxtron FOT Lab Kit, accuracy 0.2 °C, sample frequency 1 Hz), and a water-cooled solenoid magnetic coil attached to a Magnetic AC Hyperthermia (MACH) system made by Resonant Circuits Ltd. Figure 2 shows a schematic drawing of the setup used, which conforms to published descriptions of 'a typical experimental setup' [14]. Indeed, many groups working on SAR/ILP measurements report similar non-adiabatic systems in their publications (e.g [18,22,24,26,[30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49].). Some groups surround their samples with holders of varying insulating strengths, such as Styrofoam or other thermally insulating materials, while others do not [27].…”

Powerful colloidal silver nanoparticles for the prevention of gastrointestinal bacterial infections

“…In the recent decade, with the rapid development of nanotechnology, many nanoparticles and nanocomposites have been studied toward applications in treatment for endangering diseases or environments [8,9]. Among them, silver and its compounds have been used extensively in many bactericidal applications [10,11].…”

Quantum theory of plasmon energy spectra in electron gases of bulk metal and metallic nanostructures

“…It was shown that the fluctuations of the electron density in the electron gas can be described by a scalar field whose quanta are the elementary collective excitations called plasmons-the plasmon field. The present work is the continuation of the previous one [64].…”

“…In order to overcome the difficulties related to the complicated geometrical forms of the plasmonic structures, it was proposed to apply the functional integral technique using the integration and the integral equations instead of the differentiation and the differential equations in traditional quantum mechanics [64]. The formulation of the physical problems mainly in terms of the integration and the integral equations facilitates the elaboration of computational methods.…”