Optical Imaging and Magnetic Field Targeting of Magnetic Nanoparticles in Tumors

Abstract

To address efficacy issues of cancer diagnosis and chemotherapy, we have developed a magnetic nanoparticle (MNP) formulation with combined drug delivery and imaging properties that can potentially be used in image-guided drug therapy. Our MNP consists of an iron-oxide magnetic core coated with oleic acid (OA) and stabilized with an amphiphilic block copolymer. Previously, we reported that our MNP formulation can provide prolonged contrast for tumor magnetic resonance imaging and can be loaded with hydrophobic anticancer agents for sustained drug delivery. In this study, we developed MNPs with optical imaging properties using new near-infrared dyes to quantitatively determine their long-term biodistribution and tumor localization with and without an external magnetic field in mice with xenograft breast tumors. MNPs localized slowly in the tumor, reaching a peak 48 h post injection before slowly declining over the next 11 days. One-hour exposure of the tumor to a magnetic field further enhanced MNP localization to tumors. Our MNPs can be developed with combined drug delivery and multimodal imaging properties to improve cancer diagnosis, provide sustained treatment, and monitor therapeutic effects in tumors over time.

Nanotheranostics – a review of recent publications

“…Many folds of imaging-contrast properties and superior hyperthermia effect were furthermore provided over time under alternating magnetic field by the drugloaded formulation of F127250, compared to pure magnetic NPs and β-cyclodextrin-coated NPs. Similar work with a utilization of Pluronic F127 was also reported, 21 in which polymer was coated on magnetic NPs to provide prolonged contrast property in MRI with higher loading of hydrophobic anticancer agents for sustained drug delivery. Specifically, five different NIR dyes were systematically investigated to determine, in mice, the long-term biodistribution and tumor localization with and without an external magnetic field.…”

“…In a recent study carried out by Hu et al 14 the photothermal effect of AuNR was efficiently improved by a surrounding silver shell (AuNR-in-shell). The Chemotherapy X-ray imaging MR imaging [19][20][21][22][23][24][25] [27]…”

Surface engineered antifouling optomagnetic SPIONs for bimodal targeted imaging of pancreatic cancer cells

“…Among the most commonly used nano CAs, superparamagnetic iron oxide nanoparticles (SPIONs) are of particular interest for their good biocompatibility, superior magnetic resonance (MR) T 2 (transverse relaxation) shortening effects, and biodegradability. [3][4][5][6] Furthermore, SPIONs exhibit large surface areas, making them favorable for versatile surface functionalization and conjugation of biomolecules. 7,8 Two most extensively used methods in preparing SPIONs for magnetic resonance imaging (MRI) are coprecipitation and thermal decomposition.…”

Experimental and Theoretical Study of Low-Dimensional Iron Oxide Nanostructures

“…Particles larger than 50 nm show superparamagnetic iron oxides (SPIO), whereas particles smaller than 50 nm show ultrasmall superparamagnetic property (USP). The smaller ones have the ability to enhance signal detection and increase resolution in the MRI (Foy et al, 2010;Tong et al, 2010). Therefore, the SPIO particles can be used for imaging tumors in the liver and spleen, while superparamagnetic particles for contrast agents for lymphography and angiography.…”