Ammonium Bisphosphonate Polymeric Magnetic Nanocomplexes for Platinum Anticancer Drug Delivery and Imaging with Potential Hyperthermia and Temperature-Dependent Drug Release

Novel magnetite-ammonium bisphosphonate graft ionic copolymer nanocomplexes (MGICs) have been developed for potential drug delivery, magnetic resonance imaging, and hyperthermia applications. The complexes displayed relatively uniform sizes with narrow size distributions upon self-assembly in aqueous media, and their sizes were stable under simulated physiological conditions for at least 7 days. The anticancer drugs, cisplatin and carboplatin, were loaded into the complexes, and sustained release of both drugs was observed. The transverse NMR relaxivities (r2s) of the complexes were 244 s−1 (mM Fe)−1 which is fast compared to either the commercial T2-weighted MRI agent Feridex IV® or our previously reported magnetite-block ionomer complexes. Phantom MRI images of the complexes demonstrated excellent negative contrast effects of such complexes. Thus, the bisphosphonate-bearing MGICs could be promising candidates for dual drug delivery and magnetic resonance imaging. Moreover, the bisphosphonate MGICs generate heat under an alternating magnetic field of 30 kA·m−1 at 206 kHz. The temperature of the MGIC dispersion in deionized water increased from 37 to 41°C after exposure to the magnetic field for 10 minutes, corresponding to a specific absorption rate of 77.0 W·g−1. This suggests their potential as hyperthermia treatment agents as well as the possibility of temperature-dependent drug release, making MGICs more versatile in potential drug delivery applications.

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Novel Multifunctional Magnetic Nanoparticles：An Efficient Theranostic Platform for Magnetic Resonance Imaging and Targeted Therapy of Cervical Cancer

10.21203/rs.3.rs-957553/v1 ◽

2021 ◽

Author(s):

Shu Yao ◽

Li Li ◽

Chang Liu ◽

Ziying Wang ◽

Hong Liu ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Field ◽

Cervical Cancer ◽

Magnetic Resonance ◽

Drug Release ◽

Tumor Targeting ◽

Resonance Imaging ◽

Tumor Killing

Abstract Background: The high incidence and mortality rates of cervical cancer pose a serious threat to women's health. Traditional chemotherapy has inevitable drawbacks of nonspecific tumor targeting, high toxicity, and poor therapeutic efficiency. In order to overcome these shortcomings, a novel multifunctional magnetic nanoparticles drug delivery system with tumor targeting and magnetic resonance imaging was developed to achieve precise diagnosis and targeted tumor killing effects.Methods: Transmission electron microscopy, dynamic light scatting and ultraviolet methods were used to characterize the nanoparticles in vitro. Cell function tests were performed by scratch, transwell and flow cytometry assays. MTT was used to detect the toxicity of the nanoparticles. The motion trajectory, drug release and uptake studies were carried out in vitro. The in vivo pharmacokinetic and drug distribution studies were verified by high performance liquid chromatography methods. Attenuation of the MRI signal by the nanoparticles and their enhanced antitumor efficiency were examined in vivo in mouse cervical cancer models. Sequencing and proteomics were used to detect the key antitumor molecules of the nanoparticles.Results: Multifunctional magnetic nanoparticles coated with ferric oxide nanoparticles and doxorubicin hydrochloride (DOX-Fe3O4-PEG-PLA-NPs) was prepared successfully. No toxicity was detected of PEG-PLA-NP, however, the tumor killing effect was enhanced under the alternating magnetic field significantly. The drug-release study showed that the cumulative release rates of NP groups were much less than free DOX group, while the drug release rate increased under acidic condition. In addition, DOX-Fe3O4-PEG-PLA-NPs showed improved internalized into carcinoma cells under magnetic field significantly. In vivo studies demonstrated that the combined therapy under an alternating magnetic field displayed improved therapeutic effect when compared with individual therapies as documented by the delayed tumor growth, inhibition of metastasis, and prolonged survival. The in vitro and in vivo MRI results showed that the multifunctional magnetic nanomaterial had a better MRI signal reduction effect and a higher T2 relaxation rate.Conclusions: We developed an cervical cancer targeting nano-carrier drug delivery system successfully, which showed perfect excellent T2 contrast magnetic resonance imaging, chemotherapy-sensitizing, tumor targeting , and anti-tumor effect, thus have the potential to be a new theranostic strategy for ovarian cancer patients.

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SynchroMed II Intrathecal Pump Memory Errors Due to Repeated Magnetic Resonance Imaging

January 2018 - Pain Physician ◽

10.36076/ppj.2012/15/475 ◽

2012 ◽

Vol 6;15 (6;12) ◽

pp. 475-477

Author(s):

Rodolfo Gebhardt

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Field ◽

Drug Delivery ◽

Magnetic Resonance ◽

Withdrawal Symptoms ◽

Normal Operation ◽

Resonance Imaging ◽

Drug Infusion ◽

New Device ◽

Refractory Pain

Cancer patients with severe refractory pain are often managed with implantable drug delivery systems (IDDS). The only drugs with US Food and Drug Administration approval for intrathecal use are morphine, ziconotide, and baclofen. Other drugs used and mixed include, hydromorphone, bupivacaine, sufentanil, and fentanyl. These patients often undergo magnetic resonance imaging (MRI) for disease-related monitoring and diagnoses. Although uncommon, IDDS can fail to resume normal functioning after MRI, potentially causing complications. The magnetic field of an MRI will temporarily stop the rotor of the pump motor and suspend drug delivery for the duration of the MRI exposure. The pump should resume normal operation when removed from the MRI magnetic field, but there is a potential for a delay in the return of proper drug infusion and a delay in the logging of motor stall events after an MRI in the SynchroMed II pumps. A 57-yearold man who underwent multiple MRIs with an implanted IDDS experienced 2 separate memory failures leading to multiple complications. After the first pump malfunction, the patient developed withdrawal symptoms and was treated in the emergency department. The first time, a memory reset resolved the problem. The second time, 29 months later, the patient was admitted to the hospital to manage withdrawal symptoms and the pump had to be exchanged with a new device. Post-MRI pump interrogation should be performed on all patients with IDDS to ensure proper functioning of the pump. Special attention should be paid to patients receiving baclofen, as acute withdrawal can be very serious, even deadly. Key words: Cancer pain, MRI, IDDS, SynchroMed II, baclofen, withdrawal, stall.

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Magnetic Resonance Imaging of Polymeric Drug Delivery Systems in Breast Cancer Solid Tumors

10.21236/ada439254 ◽

2005 ◽

Author(s):

Bahar Zarabi ◽

Hamid Ghandehari

Keyword(s):

Breast Cancer ◽

Magnetic Resonance Imaging ◽

Drug Delivery ◽

Magnetic Resonance ◽

Solid Tumors ◽

Drug Delivery Systems ◽

Resonance Imaging ◽

Polymeric Drug Delivery ◽

Polymeric Drug ◽

Polymeric Drug Delivery Systems

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TEA-assistant synthesis of MOF-74 nanorods for drug delivery and in-vitro magnetic resonance imaging

Microporous and Mesoporous Materials ◽

10.1016/j.micromeso.2021.110900 ◽

2021 ◽

Vol 315 ◽

pp. 110900

Author(s):

Jiaqi Hu ◽

Yi Chen ◽

Hui Zhang ◽

Zhenxia Chen ◽

Yun Ling ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Drug Delivery ◽

Magnetic Resonance ◽

Resonance Imaging

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Magnetic resonance imaging: effects of magnetic field strength.

Radiology ◽

10.1148/radiology.151.1.6701302 ◽

1984 ◽

Vol 151 (1) ◽

pp. 127-133 ◽

Cited By ~ 57

Author(s):

L E Crooks ◽

M Arakawa ◽

J Hoenninger ◽

B McCarten ◽

J Watts ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Field ◽

Magnetic Resonance ◽

Field Strength ◽

Magnetic Field Strength ◽

Resonance Imaging

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MRI Susceptibility Artefacts Related to Scaphoid Screws: the Effect of Screw Type, Screw Orientation and Imaging Parameters

Journal of Hand Surgery (European Volume) ◽

10.1054/jhsb.2001.0717 ◽

2002 ◽

Vol 27 (2) ◽

pp. 165-170 ◽

Cited By ~ 30

Author(s):

M. GANAPATHI ◽

G. JOSEPH ◽

R. SAVAGE ◽

A. R. JONES ◽

B. TIMMS ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Field ◽

Titanium Alloy ◽

Magnetic Resonance ◽

Main Magnetic Field ◽

Resonance Imaging ◽

Metal Implants ◽

Imaging Parameters ◽

Susceptibility Artefact

Metal implants produce susceptibility artefacts in magnetic resonance imaging. We have explored the effects of scaphoid screw characteristics and orientation on MR susceptibility artefact. Titanium alloy, smallness and longitudinal alignment with the z-axis of the main magnetic field reduce the size of the susceptibility artefact.

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