|
Title of the Congress : |
6th international conference on nanotechnology(ICN2017) |
|
Title of your Abstract : |
Application of G4 dendrimer coated iron oxide nanoparticles in magnetic hyperthermia |
|
Destination Country : |
United Arab Emirates |
|
From : |
Thursday, February 9, 2017 |
|
To : |
Friday, February 10, 2017 |
|
Abstract(Please copy/paste the abstract send to the congress) : |
Introduction
Recently, hyperthermia has been increasingly applied in the cancer treatment since it has favorable advantages compared with other treatments including chemotherapy and radiotherapy. Iron oxide magnetic nanoparticles are used in magnetic bioseperation, clinical diagnosis and therapy including MRI and magnetic hyperthermia thanks to their very low toxicity and good biocompatibility. The polyamidoamine (PAMAM) dendrimer coated iron oxide magnetic nanoparticles(MNPs) have internal cavities makes them suitable for application in multidisciplinary cancer treatments. Dendrimers are a group of highly branched spherical polymers that are synthesized with structural equaling traditional biomolecules including DNA and RNA and are denoted as “artificial proteins”. In this study, we assessed fourth generation of PAMAM coated Fe3O4 NPs (G4@ SPIONs) in magnetic hyperthermia.
Main Text
Fe3O4 MNPs were synthesized by coprecipitation of Fe3+ and Fe2+ solution followed by surface modification with PAMAM dendrimers. The morphology and properties of obtained nanoparticles were characterized by XRD, FT-IR, TEM and DLS. In vivo and in vitro toxicity was assessed as well as hemolysis. The G4@Fe3O4 displayed relatively high magneto-temperature response which could be applied to magnetic hyperthermia therapy. Radiofrequency absorption of G4@SPIONs were assessed by specific absorption rate (SAR) defined as the amount of the heat induced per unit mass of the magnetic nanoparticles per unit of time (ΔT/Δt). Hyperthermia research system (LABA, HT-1000W, NATSYCO) with frequency range of 100-400 kHz was used to apply alternating magnetic field. The experiment was performed inside a copper coil (diameter 6 cm). The temperature for the experiments was measured by a thermocouple thermometer with a TEF-30-T thermocouple. Nanoparticles solution in an Eppendorf microtube (200µl) was inserted inside the water- cooled magnetic induction coil of the system. The temperature rise was measured by a digital thermometer and plotted against the time (temperature- time curve). The temperature rise versus time was measured in frequency of 300 kHz in two field intensities of 8 and 12 kA/m. The SAR values were calculated by equation below:
SAR=(1/mFe )C[∆T/∆t]
mFe is mass of iron in sample, C is specific heat capacity of suspension and the las term is initial slop of temperature-time curve. Thermoablation by G4@SPIONs was also investigated in cultured cancer cells. MCF7 cells were incubated with 500 µg/ml of G4@SPIONs for 2 h followed by 2 h of magnetic field exposure (300 KHz, 12 kA/m). Cells were also treated with G4@SPIONs or AMF alone, or media only. Immediately after hyperthermia, cytotoxicity was measured among the treatments.
The size of nanoparticles was approximately 10 nm and the result of DLS shown 108 nm hydrodynamic size. For clinical applications, NPs must be toxic as low as possible. Our results shown that G4@SPIONs were very low toxic in cancer and normal cell lines and this can be due to dendrimer coating of NPs and PEGylation. The cytotoxicity of G4@SPIONs was negligible. Hepatic factors as well as blood proteins did not change significantly in Balb/c mice but Renal factors including creatinine and blood urea nitrogen increased at concentration of 10 mg/ml. The highest amount of Hemolysis was only 8% at concentration of 1 mg/ml.
Application of iron oxide nanoparticles in hyperthermia depends on the heating efficiency of NPs which is assessed by specific absorption rate. Higher heat transfer and SAR were observed at frequency of 300 kHz. The starting temperature was considered to room temperature (figure 1).
AMF exposure demolished MCF7 cells significantly in comparison to control groups which were exposed to nanoparticles or hyperthermia alone. Cells that were treated with particles but without exposing to the magnetic field were unaffected, even at much as expected, control cells that were exposed to the magnetic field in the absence of NPs showed no decrease in the cell viability. In this experimental setup, cancers cells were abolished by the temperature rise due to G4@SPIONs heating under AMF(figure 2).
Conclusion
There are some studies that focused on G4@SPIONs as an MRI contrast agent or a vehicle for drug delivery. Considering to suitable magnetization properties of these NPs, we decided to investigate them in magnetic hyperthermia. For clinical use of produced NPs, they must be toxic as low as possible. Our results shown that G4@SPIONs were very low toxic in cancer and normal cell lines and this is due to dendrimer coating of NPs and PEGylation. Because of dendrimers superior properties in MRI and drug delivery, they can be suitable candidate to consider as an appropriate coating for magnetite NPs using in magnetic hyperthermia. More hyperthermia studies with G4@SPIONs are needed to elucidate this subject. |
|
Keywords of your Abstract : |
Magnetic hyperthermia, G4 dendrimer, iron oxide nanoparticles |
|
Acceptance Letter : |
http://gsia.tums.ac.ir/images/UserFiles/36321/Forms/762/acceptCard.pdf |
|
The presentation : |
Poster |
|
The Cover of Abstract book : |
http://gsia.tums.ac.ir/images/UserFiles/36321/Forms/762/book.pdf |
|
Published abstract in the abstract book with the related code : |
http://gsia.tums.ac.ir/images/UserFiles/36321/Forms/762/abstract_in_book.pdf |
|
Where has your abstract been indexed? : |
ISI |
|
If you choose other, please name : |
|