The potential of nanotechnology for diverse applications from biology to computers has been identified in recent years. With the advent of new nanomaterials for example magnetic nanoparticles, graphene, graphene oxides, gold nanomaterials, quantum dots, and etc., the field of nanotechnology is gaining more attention of scientists and researchers in this modern day world. Among many magnetic nanoparticles, superparamagnetic iron oxide nanoparticles (SPIONs - Fe3 O4 /Fe2 O3 ) have occupied a permanent position in different biomedical applications such as magnetic targeting in cancer drug delivery, contrast agents for magnetic resonance imaging (MRI), and therapeutic agents for magnetic hyperthermia.
For example, in MRI, the SPIONs provide negative contrast to specific tissues/cells where these nanoparticles are accumulated using magnetic targeting, so that minute details about the normal and cancer tissues can be conspicuously imaged and the diseases in those tissues can be diagnosed precisely. Feridex, Endorem, Combidex and Sinerem are some of the commercially available and approved MRI contrast agents. Moreover, through these iron oxide nanoparticles, heat can be generated inside the drug resistant cancer cells in order to induce apoptosis (a death inducing process), after the internalization of magnetic nanoparticles into these cells, by applying alternating magnetic field. SPIONs can be encapsulated into a polymeric micelle system with other drugs/channel blockers/imaging agents to provide a multi-functional approach to efficiently diagnose and kill the drug-resistant cancer cells in a site-specific manner. However, synthesizing the high-quality SPIONs and preserving their optimal magnetic properties for effective cancer theranostics (therapy and diagnostics) are the major research problems. Moreover, the incorporation of multiple theranostic agents in a one-pot polymeric micelle based nanoparticulate system is another research problem.
So, the significant focus of our research is “to inhibit cancer multi-drug resistance by targeted delivery of a novel and multifunctional magneto-polymeric nanoparticulate system by co-encapsulating SPIONs with channel blockers and appropriate chemotherapeutic drugs to implement combined cancer theranostics”.
SUMMARY OF OUR RESEARCH
To synthesize high-quality hydrophilic/hydrophobic SPIONs through facile chemical synthesis routes by using novel surfactants
To co-encapsulate SPIONs, channel blockers, and chemo-drugs within micelles for subsequent functionalization with antibodies, fluorescence tags, and radioactive nuclides to produce a multifunctional magnetic nanoparticulate system for effective tumor theranostics.
In our research, the high-crystalline SPIONs have exhibited high magnetic saturation (M S : 73-86 emu/g) and low cytotoxicity towards normal cells. Moreover, the SPIONs have displayed an enhanced r 2 * relaxivity (451-735 mM –1 s –1 ), high SAR values (135-500 W/g), resulting in excellent MR imaging contrast and about 60-80% tumor cell death.