Magnetic Nanoparticles Create Hot Spots in Polymer Matrix for Controlled Drug Release

Abstract

Herein, original magnetic drug delivery nanomaterials for cancer therapy are developed and compared, with the purpose to show active control over drug release by using an alternative magnetic field (AMF). The rationale is to combine polymers and superparamagnetic nanoparticles to trigger such drug release under AMF. Two magnetic nanosystems are thus presented: magnetic nanogels made of thermosensitive and biocompatible polymers and core-shell nanoparticles with a magnetic core and a molecularly imprinted polymer as shell. Both encapsulate doxorubicin (DOX) and the DOX controlled release was investigated in vitro and in cells under AMF excitation. It confirms that the local heat profile at the vicinity of the iron oxide core can be used for the DOX controlled release. It also shows that both nanosystems help delivering more DOX inside the cells compared to internalization of free DOX. Finally, the DOX intracellular release could be remotely triggered under AMF, in athermal conditions, thus enhancing DOX cytotoxicity.

Developments of Smart Drug-Delivery Systems Based on Magnetic Molecularly Imprinted Polymers for Targeted Cancer Therapy: A Short Review

“…However, the employment of MMIPs as carriers of anticancer agents is emerging. Only a few publications reported the development of MMIPs with the aim of smart delivery of anticancer drugs local to the tumor [ 3 , 50 , 54 , 61 , 65 , 68 , 77 , 78 , 79 , 80 , 81 ] that shed light on the development of a novel generation of multifunctional hybrid DDSs and future perspectives in this field.…”

“…The Griffete group utilized this feature in their imprinting process to obtain DOX-loaded MMIPs for drug delivery. They performed the functionalization of MNPs by merely growing a thin polymer layer of acrylic acid (AA) monomers on their surface, forming a molecule monolayer with polymerizable vinyl end groups [ 68 , 77 ]. The process is a simple complexing reaction of AA with unsaturated iron ions of the MNP surface.…”

Perspectives of Molecularly Imprinted Polymer-Based Drug Delivery Systems in Cancer Therapy

“…Two magnetic nanosystems for DOX controlled release were developed and tested in vitro and on human prostatic cancer cells (PC-3 cancer cells) under AMF excitation. The first one was represented by magnetic nanogels made of thermosensitive and biocompatible polymers ( Figure 6A), loaded with the antitumoral drug, and the second one was based on magnetic core DOX-imprinted polymeric shell NPs ( Figure 6B) [87]. In this case, both magnetic nanogels and NPs act as individual "hot spots" to generate localized heating that triggers the release of DOX without raising the global temperature.…”

“…Loading and release of DOX under an alternative magnetic field. Reproduced with permission from[87].…”

Thermosensitive Nanosystems Associated with Hyperthermia for Cancer Treatment

“…In order for the nanomaterials to exhibit such a response, either iron oxide or gold can be incorporated in the form of nanoparticles to the polymer matrix [79]. Iron oxide-based magnetic nanoparticles are extensively investigated in nanomedicine for their biocompatibility, their contrast agent properties, and their ability to generate heat when submitted to an alternating magnetic field [80,81]. Wang et al designed a multiple magnetic hyperthermia-mediated release system for combination therapy using an injectable, biodegradable, and thermosensitive polymeric hydrogel [82].…”