Magnetically Guided Theranostics: Optimizing Magnetic Resonance Imaging with Sandwich-Like Kaolinite-Based Iron/Platinum Nanoparticles for Magnetic Fluid Hyperthermia and Chemotherapy

Abstract

Hepatocellular carcinoma (HCC) is a common type of liver cancer that can be diagnosed by magnetic resonance imaging (MRI). If diagnosing HCC by basic MRI is difficult, then doctors use T 1-weighted or T 2-weighted imaging with a contrast agent that has long-term retention in the liver, such as Fe3O4 or FePt, to aid in MRI diagnosis. One challenging goal of cancer prevention is developing a method that can further treat or inhibit HCC cells at the time of diagnosis. Functionalized porous kaolinite can serve not only as a drug delivery system for treating cancer cells but also as a scaffold to carry FePt nanoparticles (FePt NPs) and drugs such as doxorubicin (Dox). FePt NPs combined with kaolinite modified with cetyltrimethylammonium bromide (CTAB) can form FePt@Kao nanocomposites. Multifunctional FePt@Kao can serve as a magnetic fluid hyperthermia (MFH) agent that can also be used to simultaneously visualize and treat HCC cancer cells. After being loaded with the chemotherapeutic drug Dox, FePt@Kao-Dox can provide both MFH treatment and chemotherapy. From the systematic analysis results, we demonstrated that this functionalized FePt@Kao-Dox nanocomposite can be successfully used as a platform to integrate MRI, magnetically guided targeting, and therapeutic treatment into a multifunctional drug delivery system.

Formation and Application of Core–Shell of FePt-Au Magnetic–Plasmonic Nanoparticles

“…The magnetization value is decreased with the increase of the Au concentration-dependent FePt-Au NPs. In order to obtain a better heating capability of FePt–Au NPs for magnetic fluid hyperthermia application, FePt-Au(0.2) has been selected for further investigation due to the fact that the heating efficiency is directly proportional to the magnetization value related to the strong dependence of the magnetic nanoparticle concentration in the core–shell nanostructure (Chan et al, 2020 ; Espinosa et al, 2020 ). So the following analyses will be focused on the FePt structures without and with Au(0.2) over FePt in order to study the effects of Au coating on the magnetic and optical performance of the FePt-based NPs.…”

“…The following are for the FePt NPs using airless synthesis with the reduction: 0.5 mmol for platinum acetylacetonate Pt(acac) 2 , 0.75 mmol for iron acetylacetonate Fe(acac) 3 , and 3.75 mmol 1,2-hexadecanediol were mixed with 30 ml of phenyl ether. After purging with argon for 0.5 h at room temperature, the flask was heated up to 100°C for 0.5 h with additive oleic acid (OA, 0.75 mmol) and oleylamine (OL, 0.5 mmol) stabilizers into the flask at the same time (Wei et al, 2017 ; Lin et al, 2018 ; Chan et al, 2020 ). Then, the mixture was heated up to 260°C for 1 h to form FePt NPs.…”

“…Compared with non-magnetic NPs, magnetic NPs provide a characteristic of flexible constitution on controlling and manipulation by an external magnetic field to satisfy more biomedical assays. Recently, chemically synthesized iron-based NPs and related core–shell NPs in organic solvents have been extensively studied including fundamental and functional interests due to their attractive optical, electronic, photocatalytic, biological, energy-saving, magnetic resonance imaging (MRI), and magnetic–plasmonic applications (Yavuz et al, 2006 ; Gao et al, 2007 ; Zeng and Sun, 2008 ; Levin et al, 2009 ; Chou et al, 2010 ; Wei and Yao, 2011 ; de la Presa et al, 2012 ; Chen et al, 2013 ; Seemann and Kuhn, 2014 ; Zhuang et al, 2015 ; Mandal and Chaudhuri, 2016 ; Shu et al, 2017 ; Nemati et al, 2018 ; You and Guo, 2019 ; Chan et al, 2020 ). So the simple and reproducible methods to control the crystallite size, composition, and related nanoshell coatings over the magnetic core with tunable plasmonic surface characteristics of the core–shell NPs are very important due to the fact that all potential developments are directly dependent on such corresponding magnetic–plasmonic character statements (Xu et al, 2007 ; Li et al, 2020a ).…”

“…The advantage of the solution-phase synthesis is control over the particle size and its distribution close to atomic scale and atomic precision, which strongly affects the chemical stability and biocompatibility of the synthesized NPs. Magnetic iron–platinum (FePt) NPs have suitable magnetocaloric ability to provide enough heating energy and thus destroy cancer cells for potential applications in chemotherapy and magnetic fluid hyperthermia (MFH) (Chou et al, 2010 ; Chan et al, 2020 ).…”

“…The use of Au–Fe oxide NPs as heat generators was reported to combine with magnetic hyperthermia (MHT) and photothermal therapy (PTT) protocols, according to varied parameters such as magnetic and plasmonic NP design, NP concentration, and exposure settings, which have emerged as a promising biomedical manipulation (Espinosa et al, 2020 ). Herein, we propose the magnetic–plasmonic FePt–Au core–shell NPs that can be used as a potential heating agent for applications such as cancerous or tumor hyperthermia (Chen et al, 2013 ; Chan et al, 2020 ). Therefore, the Au shell could provide several advantages as a functional coating on the core surface due to its low chemical reactivity and excellent ability to form self-assembled monolayers (SAMs) on their surface structure by using organic alkanethiol radicals, meaning long-chain thiols on gold (Sun et al, 2008 ).…”