Introduction: Nano-drug carriers have the optimized properties to facilitate the penetration into the cells, enhance the effectiveness of drugs and protect the drugs against damages caused by enzymes agents. They minimize the side effects by efficiently delivering the drugs to the cancerous cells. Chitosan is widely used in pharmaceutical industry due to its characteristics including cationic properties, dissolving in aquatic environment, bio-compatibility, and bio-degradability. As the process of creating the nano-sized chitosan particles is not difficult, they can be used as nano-carriers to carry proteins, enzymes, and drug to cancerous cells. Furthermore, chitosan is able to interact with siRNA so as the amine groups in the chitosan have high cation charge that can electrostatically interact with negative charge of phosphate group in siRNA and neutralize its negative charge. The chitosan coating in nano-carriers increases cellular absorption of siRNA. The prescription of siRNA in in vivo using nano-particles based on chitosan has resulted in 80% reduction in expression the target gene and consequently causing death of cancerous cell. The magnetic nano-particles are significantly considered to carry drugs and scientific applications. Such nano-particles are able to be attracted by the magnet. The magnetic carriers have greater efficiency in cell absorption. For this purpose, the nano-particles of mediator metals including the pure iron, cobalt, or their combinations such as FeCo can be used. This group of metal nano-particles have high tendency to maintain the magnetic torque and attract the magnetic field. Although the toxicity of cobalt is the major problem of its application, cobalt is beneficial for body at low amounts, necessary to form the vitamin B12, used to cure Anemia disease, and the cobalt combinations are not accumulated and excreted from body. In this research, the nano-particles of FeCO@SiO2-SS-Chitosan were designed and prepared to evaluate the effects of these new nano-particles on interactions with siRNA-FAM and transfection of AGS cells using the nano-particles of FeCO@SiO2-SS-Chitosan/siRNA-FAM. The new type of nano-particles was introduced to improve the identification and curing agents of cancerous cells.
Methods: In this experimental study, an appropriate quantity of FeO(OH) and Co3O4 were separately dissolved to synthesize the nano-particles of FeCO, then 200 mg of nano-particles of FeCO was sonicized in ethanol for 15 minutes to synthesize FeCO@SiO2-SS-Chitosan. One ml of each NH3.H2O, MPTMS and TEOS were added to nano-particle of FeCO under sonication conditions. Afterwards, chitosan was added to FeCO@SiO2-SS-COOH. The created nano-particles were assessed using various methods including XRD spectroscopy, TGA, transmission electron microscopey (TEM), and DLS instrument. The ability of nano-particles of FeCO@SiO2-SS-Chitosan/siRNA-FAM in transferring RNA without coating into the AGS cells was assessed by Fluorescence microscope. Agarose gel electrophoresis was used to validate the capability of nano-particles of FeCO@SiO2-SS-Chitosan to interact with siRNA-FAM.
Results: In this investigation, the cover effects on the magnetic properties, structures and size of the synthesized nano-particles were evaluated. The results of XRD spectroscopy showed that crystallization degrees for nano-particles of FeCO@SiO2-SS-Chitosan were the same as that of FeCO and chitosan, also nano-particles of FeCO led to the reduction in crystallization degree. The results of TGA spectroscopy represented that the weight decrease of nano-particles of FeCO@SiO2-SS-Chitosan were in the temperature ranges of the weight reduction of FeCO and chitosan. The results of TEM microscopy showed that the nano-particles of FeCO@SiO2-SS-Chitosan have the spherical shape with the size of approximately 20 nm. Moreover, the results of DLS instrument agreed well with those of TEM microscopy. According to the studied in the capability of interaction of nano-particles of FeCO@SiO2-SS-Chitosan with siRNA-FAM, the results acquired from agarose gel showed that nano-particles of FeCO@SiO2-SS-Chitosan/siRNA-FA with the ratio of 5 mg higher than nan-particles of FeCO@SiO2-SS-Chitosan completely neutralized the negative charge of RNA. The images captured by Fluorescence microscope represented the green emissions were observed in some AGS cells treated with nano-particles of FeCO@SiO2-SS-Chitosan/siRNA-FAM indicating the capability of these nano-particles in transferring and releasing siRNA in these cells.
Conclusion: The synthesized nano-particles have the ability to interact with siRNA-FAM. Furthermore, these nano-particles have the capability to transfer and release siRNA in these cells. However, siRNA without coating is unable to be transferred into the AGS cells.